Establishing the Pusan Perimeter
When I hear talk of lines I always think I am hearing talk of the walls of China. The good ones are those that nature has made, and the good entrenchments are good dispositions and brave soldiers.
Dawn of 1 August found the U.S. 25th Division moving to new defensive positions south of Sangju on the central front. At 1500 that afternoon a telephone message from Eighth Army head-quarters to General Kean abruptly changed division plans. Eighth Army alerted the division for movement south to Samnangjin on the Naktong River. There it was to deny enemy movement eastward and prepare to attack westward. 
An advance party of the division headquarters left Poksong-dong an hour after midnight, 2 August. That morning General Kean and his party followed by plane, stopping at Taegu for a conference at Eighth Army headquarters. At the conference, General Walker changed the destination of the division from Samnangjin to Masan. General Kean informed the division units en route of the change in orders, employing every type of communication available, from runner to radio. 
There was only one road for the movement of the 25th Division. This ran south from Sangju to Kumch'on and then southeast to Waegwan on the Naktong River. Travel as far as Waegwan would be by foot and motor, from Waegwan to Masan by rail. The Kumch'on-Waegwan road was the main supply road to the central front. Accordingly, there was ample opportunity for conflict, confusion, and delay in the movement of supplies north and of the 25th Division south over this road. Eighth Army headquarters recognized this danger. Colonel Landrum made available from headquarters to the army G-3 Section all the officers he could spare to assist in the orderly control of the 25th Division movement. These officers concentrated their attention at points where road restrictions or the presence or movement of other units threatened trouble. 
Equal or even greater effort had to be made to assure that the necessary rail equipment would be at hand to carry the division from Waegwan southward. At the time, with the enemy pushing the front back everywhere, there was a great demand for rail equipment to evacuate supplies and troops. Congestion in rail yards was almost indescribable. Units seeking transportation commandeered locomotives, cars jammed the tracks, native refugees crowded into cars, and general chaos threatened. The ROK 17th Regiment, moving southwest at this time to buttress the sagging 24th Division front in the Koch'ang area, further complicated the traffic problem. Without the planning, supervision, and hard work of American transportation troops, the Korean rail system would have failed at this time. 
The loading of heavy equipment and weapons, such as the 155-mm. howitzers, went on all during the night of 2-3 August at Waegwan. The last of the troops arrived on trucks of the 73d Truck Company at 0530, 3 August. These dust-caked men and their equipment, loaded into boxcars and gondolas, were on their way to the new front at 0600. An hour later the last of the division equipment had been loaded into cars and was on its way to Masan. 
The main party of the 25th Division command post arrived at Masan at 2115, 2 August, after an all-day ride. Of the combat units, the 35th Infantry moved first, closing at Masan at 1000, 3 August. The 24th Infantry arrived at 1930 that evening. General Kean reached Masan during the day and assumed command of all the U.N. troops south of the Naktong River. The 25th Division completed the 150-mile move by foot, motor, and rail within a 36-hour period.
General Walker said that this "history making maneuver" saved Pusan. He said also that had the North Koreans attacked strongly on the Kumch'on front while the division was passing over the single road through Kumch'on, "we couldn't have done it." 
In recognizing the critical nature of the situation in the southwest and in acting with great energy and decisiveness to meet it, General Walker and his staff conceived and executed one of the most important command decisions of the Korean War.
By the end of July, the enemy pressure that forced General Walker to move the 25th Division from the central to the southern front forced on him also, partly as a consequence of that move, the decision to withdraw Eighth Army across the Naktong. The withdrawal was planned to start the night of 1 August. 
On 30 July the 34th Infantry of the 24th Division, driven from Koch'ang, was in a defensive position near Sanje-ri astride the road to Hyopch'on and the Naktong River. That day, the 21st Infantry Regiment-except for C Company and a section of 81-mm. mortars, still at Yongdok on the east coast, and the 3d Battalion, just attached to the 1st Cavalry Division-crossed the Naktong and took a position behind the 34th Infantry. The ROK 17th Regiment also arrived and occupied the high ground on the right (north) of the 34th Infantry. The next morning the 34th Infantry withdrew behind the 21st Infantry. Colonel Stephens then assumed command of both the 21st and the 34th Regiments on oral orders from General Church. 
After the 34th Infantry withdrew through the 1st Battalion, 21st Infantry, Colonel Stephens moved the ROK 17th Regiment back abreast of his troops, with one battalion on either flank and one in reserve. The next day, 1 August, North Koreans attacked both flanks. The ROK's repulsed them. General Church initially had intended that the ROK 17th Regiment would pass through the mountains around the flank of the North Koreans and attack from their rear while the 34th and 21st Regiments held them in front. But the army order for withdrawal came before this could be done. The ROK 17th Regiment at this time had a high reputation. Colonel Kim, the commander, a small man of twenty-eight years, commanded the respect of his officers and men. In a conference at this time, General Church asked Colonel Kim if his ROK's would hold their part of the line. He answered, "We will stay as long as the Americans." He was believed implicitly by those present. 
On 1 August Eighth Army issued an operational directive to all United Nations ground forces in Korea for their planned withdrawal behind the Naktong. It confirmed oral and fragmentary orders already issued to units on their redeployment to the main defensive positions of the Pusan Perimeter. 
At 0945, 2 August, Colonel Stephens received Eighth Army's order to withdraw. He at once sent the 34th Infantry across the Naktong to the Yongsan area. During the day, while the 21st Infantry and the ROK 17th Regiment fended off enemy probing attacks, he made plans to complete the withdrawal that night to the east side of the Naktong. 
The withdrawal east across the Naktong by the 21st Infantry proceeded smoothly during the night of 2-3 August. The last of the regiment crossed the Koryong-Taegu bridge forty-five minutes past midnight, followed by the 14th Engineer Combat Battalion two hours later. The ROK 17th Regiment, covering the withdrawal of the other units (Colonel Stephens remained with it), crossed the river at 0630, 3 August. Engineers unsuccessfully tried to blow the bridge at 0715. During the day the 3d Engineer Combat Battalion again prepared it for demolition and dropped it that night. The preceding night, at 2200, the engineers blew the other Naktong River bridge in the 24th Division sector. It was twenty air miles south of the Koryong bridge and connected Ch'ogye with Changnyong, 24th Division headquarters. 
On the evening of 3 August, the third regiment of the division, the 19th Infantry, was relieved in its position at the Chungam-ni Notch west of Masan by the 35th Infantry of the 25th Division. It then moved northeast across the Naktong to the command post of the 24th Division at Changnyong, arriving there the next day. From the time of its commitment in Korea on 13 July to 4 August, the 19th Regiment had lost 80 per-cent of its 1/4-ton trucks, 50 percent of its 3/4-ton trucks, and 33 percent of its 2 1/2-ton trucks. Low on all supplies, it found individual clothing, hand grenades, 4.2-in. mortar ammunition, and flares and illumination shells all but impossible to obtain. 
Simultaneous with the movement of the 24th Division to the east side of the Naktong, the 1st Cavalry Division, next in line above it, began withdrawing on army orders from the Chirye-Kumch'on area to Waegwan on the east side of the river. The division withdrew without difficulty, except for the 5th Cavalry Regiment. This regiment, the last in the march order, was heavily engaged and one battalion nearly lost. By nightfall of 3 August, however, all units of the division were across the Naktong except the rear guard of the 1st Battalion, 8th Cavalry Regiment, which had been blocking on the Songju road, southwest of the Waegwan bridges. 
The main line railroad bridges and the highway bridge across the Naktong at Waegwan were to be blown as soon as all units of the 1st Cavalry Division had crossed. These bridges were the most important on the river. General Gay, in arranging for their destruction, gave orders that no one but himself could order the bridges blown. At dusk on 3 August, thousands of refugees crowded up to the bridges on the west side of the river, and repeatedly, as the rear guard of the 8th Cavalry would start across the bridge, the mass of refugees would follow. The division commander ordered the rear guard to return to the west side and hold back the refugees. When all was ready the troops were to run across to the east side so that the bridge could be blown. This plan was tried several times, but in each instance the refugees were on the heels of the rear guard. Finally, when it was nearly dark, General Gay, feeling that he had no alternative, gave the order to blow the bridge. It was a hard decision to make, for hundreds of refugees were lost when the bridge was demolished. 
The refugee problem was a constant source of trouble and danger to the U.N. Command during the early part of the war. During the middle two weeks of July it was estimated that about 380,000 refugees had crossed into ROK-held territory, and that this number was increasing at the rate of 25,000 daily. The refugees were most numerous in the areas of enemy advance. In July and August 1950, the volume of refugees moving through U.N. lines was greater than at any other time in the war.
With the destruction of the Waegwan bridges, Eighth Army by the morning of 4 August had destroyed all the bridges across the Naktong on its front. Its troops were in defensive positions on the east bank awaiting enemy crossings.
On a line curving north and east from Waegwan, the divisions of the ROK Army also withdrew across the river, co-ordinating their moves with Eighth Army on the night of 2-3 August. In this movement, the ROK forces had some severe fighting. The ROK 1st Division was heavily engaged north of the river on 2 August, while the 16th Regiment of the ROK 8th Division was even more heavily engaged by the N.K. 12th Division at Andong. 
It was evident in the last days of July and the first of August that General Walker was concerned about the failure of his troops to carry out orders to maintain contact with the enemy. In preparing for the withdrawal to the Perimeter position, on 30 July he had ordered all units to maintain such contact. Three days later conditions compelled him to repeat the order with the injunction that division commanders give it their personal attention. Later in the day he thought it necessary to issue still another directive which ordered, "Daily counterattacks will be made by all units. ... Commanders will take immediate and aggressive action to insure that these and previous instructions to this effect are carried out without delay." "Counterattack," Walker said, "is a decisive elm [element] of the defense." 
The Naktong River Line, as many called it, was the vital position where Eighth Army intended to make its stand. On 4 August, General Church issued to the 24th Division an order typical of those issued to American troops at this time. He directed that every man in the division know the order. It said:
The Pusan Perimeter positions taken up by the American and ROK forces on 4 August enclosed a rectangular area about 100 miles from north to south and about 50 miles from east to west. (See Map IV.) The Naktong River formed the western boundary of the Perimeter except for the southernmost 15 miles below the point where it turned eastward after its confluence with the Nam. The Sea of Japan formed the eastern boundary, and the Korea Strait the southern boundary. An irregular curved line through the mountains from above Waegwan to Yongdok formed the northern boundary. Yongdok on the east coast stood at the northeast corner of the Perimeter, Pusan was at the south-east corner, Masan at the southwest corner, and Taegu near the middle from north to south, but only about 10 miles from the western and threatened side of the Perimeter. From Pusan, Masan is 30 air miles west, Taegu 55 miles north-west, P'ohang-dong 60 miles northeast, Yongdok 90 miles northeast. With the exception of the delta of the Naktong and the east-west valley between Taegu and P'ohang-dong, the ground is rough and mountainous. The mountains are particularly forbidding in the northeast above P'ohang-dong.
In planning for the defense of the Perimeter, Eighth Army believed it needed at least two reserve forces, one in the vicinity of Kyongsan, 10 miles southeast of Taegu, which it could use to bolster any part of the line in the center and in the P'ohang-dong area of the east coast, and another in the vicinity of Samnangjin-Miryang, which it could use against any threatened or actual enemy breakthrough along the lower Naktong or the Masan corridor. 
General Walker reported to the Far East Command at this time that he thought the 24th Division would have to be completely rehabilitated before it could be effective. He also doubted that the 25th Division had offensive capabilities. He intended to use the 30,000 ROK trainees, he said, mostly to bring the existing ROK divisions to full strength. After that was done, he would begin the organization of new ROK divisions. 
The deployment of U.N. forces on the arc curving from the southwest to the northeast as the battle of the Perimeter opened was as follows: U.S. 25th Infantry Division, U.S. 24th Infantry Division, U.S. 1st Cavalry Division, and then the ROK 1st, 6th, 8th, Capital, and 3d Divisions, in that order.
In the southwest, Eighth Army had hoped to anchor the line near the coast on the Chinju pass, but the enemy had forced the line eastward to a point just west of Chindong-ni, whence it ran northward from the coast to the Nam River below Uiryong, a few miles west of the confluence of the Nam and the Naktong. The 27th, 24th, and 35th Regiments of the 25th Division were on line in that order, south to north, with some ROK's (Task Force Min) interspersed among them, particularly in the 24th Infantry sector. The division command post was at Masan.  In addition, General Kean had at hand the 5th Regimental Combat Team, attached to the 25th Division, and the 89th Medium Tank Battalion.
Opposite the 25th Division stood the N.K. 6th Division and the 83d Motorized Regiment of the 109th Armored Division.
Next on the U.N. line was the U.S. 24th Division. Its zone lay north of the Nam and along the east bank of the Naktong for 25 air miles, or about 40 miles of river front. The 34th and 21st Infantry Regiments and the ROK 17th Regiment were on line in that order, south to north. The 19th Infantry was in division reserve, re-equipping after arriving from the Masan front on 4 August. The 21st Infantry front was so long that Colonel Stephens, the regimental commander, placed seven .50-caliber machine guns with crews from the 14th Engineer Combat Battalion in the main line of resistance. The division command post had now moved to Mir-yang.
Eighth Army on 3 August defined the boundary between the 24th and 25th Divisions as the south bank of the Naktong River, and made the commanding general of the 24th Division responsible for bridges, ferries, and small boats along the stream. General Church was to remove to the north bank, and destroy as he deemed advisable, all boats and ferries, and to prepare all bridges for demolition and blow them at his discretion. At this time, Eighth Army planned for the 9th and 23d Regiments of the 2d Infantry Division to relieve the 24th Division in its sector of the line the night of 8 August, but events were to make this impossible. 
Opposite the 24th Division stood the N.K. 4th Division.
Above the 24th Division, the U.S. 1st Cavalry Division extended the line 18 air miles to a point 3 miles north of Waegwan. The actual river line was about 35 miles. The 7th Cavalry (less the 1st Battalion, which was in division reserve), the 8th Cavalry, and the 5th Cavalry Regiments were in position in the division sector, in that order from south to north. The division command post was at Taegu. Taegu, also Eighth Army headquarters, lay about 10 miles east of the Naktong River behind the center of the 1st Cavalry Division front. 
Opposite the 1st Cavalry Division was the N.K. 3d Division.
The three American divisions each had fronts to defend from 20 to 40 miles long. The Naktong River Line at this time resembled closely the German front before Moscow after the first German withdrawal in 1941, when Guderian's divisions each had a front of 25 to 35 miles to defend. 
North of Waegwan, the ROK 1st and 6th Divisions of the ROK II Corps extended the line north along the Naktong for 20 more air miles, and thence north-east for about 10 miles toward Uisong. From there the 8th and Capital Divisions of the ROK I Corps continued the line northeast through Uisong where it turned east toward Yongdok on the coast. On the east coast the ROK 3d Division held the right anchor of the U.N. line. The ROK Army headquarters was at Taegu with a forward command post at Sinnyong. ROK I Corps headquarters was at Uisong; ROK II Corps headquarters at Kunwi. 
North of Waegwan, the N.K. 15th and part of the 13th Divisions faced the ROK 1st Division; eastward, part of the N.K. 13th and the 1st Division faced the ROK 6th Division; beyond them the N.K. 8th Division stood in front of the ROK 8th Division; next in line, the N.K. 12th Division confronted the ROK Capital Division below Andong; and, finally, on the east coast the N.K. 5th Division and the 766th Independent Infantry Regiment faced the ROK 3d Division. 
In summary then, the ROK Army held the east half of the line from a point just above Waegwan; the U.S. Eighth Army held the west or southern part. The ROK sector extended for about 80 air miles; the Eighth Army's for about 65 air miles. The ROK troops held the most mountainous portions of the line and the part with the poorest lines of communications.
The North Korean Army comprised two corps: I Corps controlled operations generally along the western side of the perimeter opposite the American units; II Corps controlled operations along the northern or eastern half of the perimeter opposite the ROK units. This enemy corps alignment remained unchanged throughout the Pusan Perimeter period of the war. 
The N.K. Army had activated its I Corps at P'yongyang about 10 June 1950, its II Corps at the same place about 12 June 1950. In early August 1950, the N.K. I Corps included the 3d, 4th, and 6th (later also the 2d, 7th, 9th, and 10th) Divisions; II Corps included the 1st, 5th, 8th, 12th, 13th, and 15th Divisions. Tanks and personnel of the 105th Armored Division were divided between the two corps and supported both of them.
The establishment of the Pusan Perimeter may be considered as a dividing line in viewing and appraising the combat behavior of the American soldier in the Korean War. The Pusan Perimeter for the first time gave something approaching a continuous line of troops. With known units on their left and right and some reserves in the rear, the men showed a stronger disposition to fight. Before the Pusan Perimeter, all through July and into the first days of August, there was seldom a continuous line beyond a battalion or a regimental position. Both flanks were generally wide open, and enemy troops moving through the hills could easily turn a defensive position. Supporting troops were seldom within reach. American soldiers, realizing the isolated nature of their positions, often would not stay to fight a losing battle. Few in July 1950 saw any good reason for dying in Korea; with no inspiring incentive to fight, self-preservation became the dominating factor.
Air support, tactical and strategical, and the state of logistics at the end of July after the first month of war both exercised continuing and pervasive influence on the course of the heavy August battles of the Pusan Perimeter.
In the first month of the Korean War, close air support of ground troops was a vital factor in preventing the North Koreans from overrunning all Korea, and in gaining for the United States the margin of time necessary to bring in reinforcements and accumulate the supplies needed to organize the Pusan Perimeter. By mid-July the U.N. Air Force had all but stopped movement of enemy troops, armor, and truck convoys during daylight. This imposed the greatest difficulties on North Korea in supporting its front-line troops, and it slowed the North Korean advance.
During the first month, the U.N. air arm comprised U.S. Air Force, Navy, and Marine planes and some Royal Australian Air Force planes and troops. By the end of July, the U.N. ground forces in Korea were receiving proportionately more air support than had General Bradley's Twelfth Army Group in World War II. 
In mid-July, the FEAF Bomber Command began an ever heightening attack on strategic enemy targets far behind the front. The first such target was Wonsan on the east coast. This communications center linked Vladivostok in Russia Siberia with North Korea by rail and sea. From it, rail lines ran to all the North Korean build-up centers. The great bulk of Russian supplies for North Korea in the early part of the war came in at Wonsan, and from the beginning it was considered a major military target. In the first heavy strategic bombing of the war, FEAF hit this busy port city, on 13 July, with 400 tons of demolition bombs. Three days later, thirty B-29 bombers struck the railroad marshaling yards at Seoul. 
One of the important bomber missions was to deny the enemy use of the pontoon bridge across the Han River at Seoul, and to destroy the repaired railroad bridge there. Several attempts in July by B-29's to destroy the rail bridge failed, but on the 29th twelve bombers succeeded in hitting the pontoon bridge and reported it destroyed. The next day, forty-seven B-29's bombed the Chosen Nitrogen Plant at Hungnam on the northeast coast. 
In the meantime, carrier-based planes from the USS Valley Forge, which was operating in the Yellow Sea, on 22 July destroyed at Haeju in North Korea six locomotives, exploded eighteen cars of a 33-car train, and damaged a combination highway and rail bridge. 
By 27 July, the FEAF Bomber Command had a comprehensive rail interdiction plan ready. This plan sought to interdict the flow of enemy troops and materiel from North Korea to the combat area. Two cut points-(1) the P'yong-yang railroad bridge and marshaling yards and (2) the Hamhung bridge and Hamhung and Wonsan marshaling yards - would sever rail communications with North Korea. Destruction of the rail bridges over the Han near Seoul would cut rail communication to the battle area. On 28 July the Far East Air Forces gave to the Bomber Command a list of targets in the rail interdiction program, and two days later a similar plan was ready for interdiction of highways. On the third day of August, FEAF issued to the Fifth Air Force and to the Navy lists of targets for co-ordinated interdiction attacks south of the 38th Parallel. In general, the Han River divided Fifth Air Force and FEAF Bomber Command zones. 
By the end of July, the Far East Air Forces had flown as many as 400 sorties in a day. Altogether, it had flown a total of 8,600 sorties-4,300 in close support missions, 2,550 in close interdiction, 57 in two strategic bombing strikes, and 1,600 in reconnaissance and cargo sorties. 
As the month neared an end, the first fighter plane reinforcements from the United States reached the Far East. On 23 July, the 27,000-ton Navy carrier, Boxer, setting a Pacific crossing record of eight days and seven hours, arrived in Japan with 145 F-51 Mustangs borrowed from National Guard air squadrons.  On 30 July, the Far East Air Forces had 890 planes-626 F-80's and 264 F-51's-but only 525 of them were in units and available and ready for combat. 
Rockets, napalm, and .50-caliber machine gun fire in strafing were the effective weapons used by the close support fighter planes. Napalm, the jellied gasoline carried in wing tanks, generated a searing heat when ignited by a contact fuze upon striking the ground. The splashing, flaming liquid is a two-edged weapon: it burns and consumes, and it strikes men with terror when it bursts on or near their positions. No one who has seen the huge, podlike tanks hurtle to the ground and burst into orange balls of flame, quickly followed by billowing clouds of dense, black smoke, would care to withstand this form of attack.
The consumption of aviation gasoline was so great in the early phase of the war, as compared to the available supply in the Far East, that it became one of the serious logistical problems. Ocean tankers could scarcely keep pace with the rate of consumption. The situation never got to the point where air operations stopped, but it came near to that. There were times when the gas terminals in Japan were empty-all the fuel was in the stations. 
Just as Eighth Army prepared to fall back behind the Naktong River, important ground reinforcements from Hawaii and the United States arrived in Korea. The United States had barely won the race against space and time.
The 5th Regimental Combat Team from Hawaii, commanded by Col. Godwin L. Ordway, arrived first, on 31 July, after nine days at sea, with all three battalions. With the regiment came fourteen M26 Pershing tanks and the 555th (Triple Nickel) Field Artillery Battalion. Orders from Eighth Army awaited the regiment upon its arrival at Pusan to proceed at once to Masan where it was to be attached to the 24th Division. The leading element of the regiment arrived at Masan the next evening, 1 August. By the following morning the entire regiment was in an assembly area north of the town. 
This regiment included many Hawaiians and some former members of the famed 442d Regimental and the 100th Battalion Combat Teams, the much-decorated Nisei infantry units of World War II. Another notable characteristic of this regiment was the close bond of comradeship that existed between it and its supporting 555th Field Artillery Battalion.
Into Pusan harbor on the same day, 31 July, came the first ground troops from the United States, the 9th Infantry Regiment of the 2d Infantry Division. Known as the Manchu Regiment because of its part in suppressing the Boxer Rebellion in China in 1900, the 9th Infantry was one of the oldest regiments in the United States Army. The 2d Battalion of the regiment sailed from Tacoma, Washington, 17 July, the first Army infantry troops to depart continental United States for Korea. The 9th Infantry, commanded by Col. John G. Hill, proceeded immediately to Kyongsan, ten miles southeast of Taegu, and was placed in army reserve. The 15th Field Artillery Battalion accompanied the regiment as its artillery support unit. At 0130, 2 August, Eighth Army ordered Colonel Hill to be ready to move his regiment on 1-hour notice after 1600 that day. 
The 23d Infantry, 2d Division, began arriving at Pusan on 5 August. That very morning its 1st Battalion received an alert to be ready to move on an hour's notice. 
A third major reinforcement arrived in Korea on 2 August-the 1st Provisional Marine Brigade, commanded by Brig. Gen. Edward A. Craig. Activated on 7 July, the brigade began loading at San Diego and Long Beach, Calif., two days later and sailed for the Far East on the 14th. While still at sea it received orders to bypass Japan and head directly for Pusan. On 25 July, General Wright, Far East Command G-3, verbally ordered General Craig, who was in Japan with his advance party, to change his brigade plans from occupying the Kobe-Osaka-Kyoto area of Japan to reporting with the brigade to Eighth Army in Korea. The marines went ashore at Pusan on 3 August and proceeded immediately to Masan in Eighth Army reserve. The Marine brigade was attached to the 25th Division on 6 August. The brigade comprised the 5th Marines, commanded by Lt. Col. Raymond L. Murray, plus a brigade headquarters group. The three battalions of the regiment had only two rifle companies each and a Heavy Weapons Company. The brigade had a strength of 4,725 men. Most of the officers and about 65 percent of the noncommissioned officers of the Marine brigade were combat veterans. 
Initially, General MacArthur had planned to use the Marine brigade in an amphibious operation behind the enemy lines. The situation at the time the brigade arrived in Far Eastern waters, however, required its unloading at Pusan. Every available man, it appeared, would be needed to hold the Pusan Perimeter.
Except A Company, which already had arrived, the 8072d Medium Tank Battalion, a provisional organization equipped in Japan with repaired tanks salvaged from the Pacific island battle-fields of World War II, came into Pusan harbor on 4 August. Three days later Eighth Army transferred its troops and equipment to the 88th Medium Tank Battalion. Other tanks were on the way. The SS Luxembourg Victory left San Francisco on 26 July carrying eighty medium tanks. 
Replacements from the United States also had begun to flow into the Far East Command for assignment in Korea. In July, several hundred officer and 5,287 of 5,300 promised enlisted replacements arrived in Japan and were hurried on to Korea. The Far East Command indicated that the volume of replacements would increase during August and September and reach 16,000 in October. For the last ten days of July, the airlift brought an average of 42 officers and 103 enlisted men daily from the United States west coast, about 100 less than the 240 estimated at its inception as the airlift's daily capacity. 
The type of war materiel coming into Pusan Harbor during July shows why the United Nations Command had to hold a defense perimeter around this vital port if the North Koreans were to be denied victory.
During the period of 2-31 July 1950, a total of 309,314 measurement tons of supplies and equipment were off-loaded at Pusan, a daily average of 10,666 tons.
The first heavy lift cranes arrived on 23 July-a 60-ton crane and two crawler cranes, towed 900 miles from Yokohama. Not until the first week of August did a 100-ton crane reach Pusan. In the last half of July, Pusan was a busy port in-deed, 230 ships arriving and 214 departing during the final sixteen days of the month. During this period, 42,581 troops, 9,454 vehicles, and 88,888 long tons of supplies came ashore there. Subordinate ports of Ulsan and Suyong unloaded ammunition and petroleum products over the beaches from barges, tankers, and LCM's. 
The airlift of critically needed items from the United States tapered off at the end of July as surface transportation began to meet requirements. Some items such as the new 3.5-inch rocket were still being carried largely by airlift, 900 of them being scheduled daily for air delivery to Korea during August. The new 5-inch "shaped charge" rockets for Navy fighter planes, developed at the Navy's Inyokern, California, Ordnance Test Station, were at first delivered to Korea entirely by air. A special Air Force plane picked up at Inyokern on 29 July the first 200 of the shaped charge war-heads for delivery to the Far East. 
After the first hectic weeks, steps were taken to reduce the necessity for the large number of airlifts to Korea from Japan. By 15 July, MacArthur's headquarters sent to Eighth Army a proposal to provide daily ferry service from the Hakata-Moji area to Pusan, and to provide this service with fast express trains from the Tokyo-Yokohama area.  Accordingly, a Red Ball Express was organized. It had a capacity of 300 measurement tons daily of items and supplies critically needed in Korea. The Red Ball made the run from Yokohama to Sasebo in a little more than thirty hours, and to Pusan in a total of about fifty-three hours. The first Red Ball Express train with high priority cargo left Yokohama at 1330 23 July. Regular daily runs became effective two days later. The schedule called for the Red Ball to depart Yokohama at 2330 nightly and arrive at Sasebo at 0542 the second morning thereafter, and for the cargo to be transferred directly from train to ship. Ship departure was scheduled for 1330 daily and arrival at Pusan at 0400 the next morning. 
Army transportation men worked almost ceaselessly during July to bring order out of near chaos in the train movements from Pusan toward the rail-heads at the front. By 18 July they had established a regular daily schedule of supply trains over two routes: (1) the main Pusan-Taegu-Kumch'on line with
a branch line from Kumch'on to Hamch'ang; and (2) the Pusan-Kyongju-Andong single track line up the east coast with a branch line from Kyongju to P'ohang-dong. As the battle front moved swiftly southward, trains after the end of July did not run beyond Taegu and P'ohang-dong. After the enemy threat developed in the southwest, a supply train ran daily from Pusan t0 Masan. On 1 July the U.N. Command controlled 1,404 miles of rail track in South Korea. By the end of the month this had shrunk to 431 miles of track, a loss of 973 miles, or more than two. thirds. 
In July, 350 mixed trains moved from Pusan toward the front. These included 2,313 freight cars loaded with 69,390 short tons of supplies. Also leaving Pusan for the front were 71 personnel trains carrying military units and replacements. Among the trains returning to Pusan from the forward area were 38 hospital trains carrying 2,581 patients, and 158 freight cars loaded largely with personal belongings taken by unit commanders from their men in trying to strip them down to only combat needs. 
Since the Korean railroads had been built by Japan, repair and replacement items could be borrowed from the Japanese National Railways and airlifted to Korea within a very short time after the need for them became known. One of the largest and most important of rail purchases in Japan for use in Korea was twenty-five standard-gauge locomotives. By 1 August the ROK National Police was responsible for protecting all rail bridges and tunnels. Armed guards, their number varying with the importance of the structures, were stationed at each of them. 
The re-equipping of the ROK Army constituted in itself a large logistical problem in July. To meet part of the requirements, Japanese manufacturers contracted in August to produce for the ROK Army 68,000 vehicles, mostly cargo and dump trucks, with first deliveries to be made in September. Another matter of importance concerned replacing artillery losses in the early weeks of the war with World War II 105-mm. howitzers rebuilt in Japan. 
During the fourth week of American intervention, certain formal proceduresindicated, seemingly, that the U.N. Command expected the war to continue for some time. General MacArthur, on 23 July, announced that the U.N. Command had adopted the provisions of the 1949 Geneva Prisoner of War Convention. President Syngman Rhee in a proclamation likewise accepted the provisions of the Geneva Convention on behalf of the Republic of Korea. Then, on 24 July, General MacArthur established a formal United Nations Command with headquarters in Tokyo. The next day this headquarters issued U.N. Communiqué No. 1. 
Although American losses were heavy in the first month of the war, the build-up of U.S. men and weapons in Korea had gone steadily forward. Initially, Americans lost as many men from heat exhaustion as from gunfire. The temperature reached 110 degrees, the Naktong hills had little vegetation, and good water was scarce. There was little shade in southern Korea. The blazing sun together with the exertion required to climb the steep slopes caused frequent throbbing headaches. The men's legs lacked the power to climb the steeply pitched mountains and buckled under the unaccustomed ordeal. 
The preponderance of American battle casualties was in the Army ground forces. The Navy and Air Force had few battle casualties at this time.  American Army casualties in Korea through 31 July 1950 totaled 6,003 men: 1,884 killed, 2,695 wounded, 523 missing, and 901 reported captured. Almost 80 percent of these casualties occurred in the last half of the month.  More than half the total battle losses were in the 24th Infantry Division which up to 4 August listed 85 men killed, 895 wounded, and 2,630 missing for a total of 3,610 battle casualties. 
ROK Army losses during the first six weeks of the war were very heavy, but the precise number is unknown. Probably the killed, wounded, and missing reached 70,000. Most ROK units were in almost continuous action during July. In the United States, where the press emphasized American battle action, the part of ROK units in checking the North Korean advance was generally under- estimated and little understood. ROK Army losses were normally far greater than those of Eighth Army. On 1 August, for example, ROK casualties were 812 (84 KIA, 512 WIA, 216 MIA) in comparison with U.S. Army losses of 285, and on 3 August they were 1,133 (128 KIA, 414 WIA, 591 MIA) in comparison with U.S. Army losses of 76. 
If the estimate of 70,000 for ROK losses is approximately accurate, total U.N. losses up to 5 August 1950 would be about 76,000 men.
According to their own testimony, the North Korean losses were far greater for this period than U.S. military sources estimated them to be at the time. On 29 July, General MacArthur's Intelligence Section set the figure at 31,000. The Department of the Army estimated 37,500.  Actually, the North Korean casualties appear to have been about 58,000, according to a study of prisoner of war interrogations. This large discrepancy was due apparently to a failure on the part of American authorities to realize how great were the casualties inflicted by the ROK Army. When the enemy is advancing there is little opportunity to count his dead. In some engagements, the ROK's decimated N.K. regiments and even whole divisions.
Underestimation of enemy losses in the first five weeks of the war led in turn to an exaggerated notion of the enemy forces facing the U.N. Command along the Pusan Perimeter. The enemy had probably no more than 70,000 men in his committed eleven divisions, one independent mechanized regiment, and one independent infantry regiment, as he began crossing the Naktong River on 4-5 August to assault the U.N. forces in the Pusan Perimeter. A tabulation of estimated enemy strength by major units as of 5 August follows: 
No reliable figures are available for the number of enemy tanks destroyed and for tank troop casualties of the 105th Armored Division by 5 August, but certainly they were high. There were only a few tank replacements during July.
The first large tank replacement apparently took place about 15 August, when 21 new tanks and 200 tank crew men arrived at the front. Aerial action destroyed many new tanks before they could reach the battle zone. One captured major said the armored division was down to 20 percent strength by the time the battle for Taegu began.  The North Koreans probably had no more than 3,000 armored personnel and forty tanks at the front on 5 August.
While no exact information is available as to the number of enemy artillery pieces and heavy mortars still in action by 5 August, it probably was about one-third the number with which the North Koreans started the war. The 4th Division artillery, for instance, reportedly had only twelve guns on 5 August when the division reached the Naktong. 
An official report from General MacArthur to the Department of the Army gave U.N. troop strength in Korea on 4 August 1950 as 141,808: 
This report indicates that American ground combat units, as of 4 August, totaled more than 47,000 men. The principal ROK combat strength at this time was in five infantry divisions recently filled to a strength of approximately 45,000 men. 
Thus, on 4 August, the United Nations combat forces outnumbered the enemy at the front approximately 92,000 to 70,000.
The relative U.N. strength opposed to the North Koreans at the front in early August was actually much more favorable than commonly represented. A leading American newspaper on 26 July, in a typical dispatch filed in Korea, described the attack against the 1st Cavalry Division at Yongdong as being "wave after wave." A subhead in a leading article in the same newspaper a few days later said in part, "We are still out-numbered at least four to one."  Other American newspapers reported the Korean War in much the same vein. The claim that enemy forces outnumbered United Nations troops at least four to one had no basis in fact.
High U.S. Army sources repeated the statements that U.S. forces were greatly outnumbered. The North Korean forces had outnumbered those of the United Nations after the near collapse of the ROK Army at the end of June and until about 20 July, but never by more than two to one. By 22 July the U.N. forces in Korea equaled those of the North Koreans, and in the closing days of the month the United Nations gained a numerical superiority, which constantly increased until near the end of the year.
 25th Div WD, 1 Aug 50.  Ibid., 2 Aug 50; 24th Inf WD, 6-31 Jul 50, p. 42; 2d Bn, 24th Inf, WD, 1-31 Aug 50.  Note. by Landrum for author, recd 8 Mar 54.  See Col E. C. R. Lasher, "A Transport Miracle Saved Pusan,"  Ibid.  New York Times, August 11, 1950, AP dispatch from Korea, dated 10 August, reporting conversation of General Walker.  EUSAK WD, G-3 Sec, 28 and 31 Jul 50.  21st Inf WD, 30-31 Jul 50; 24th Div WD, 31 Jul 50; Interv, author with Beauchamp, 24 Sep 52; Ltr, Beauchamp to author, 7 Apr 53; Stephens, MS review comments, Dec 57.  Interv, author with Church, 25 Sep 52: Interv, author with Cheek, 5 Aug 51; Interv, author with Maj Charles R. Alkire (S-2, 21st Inf), 1 Aug 51; Interv, author with Col Richard W. Stephens, 8 Oct 51.  EUSAK WD, C-3 Sec, an. 3, 1 Aug 50. Annex 3 includes a copy of the directive, Plan D.  21st Inf WD, 2 Aug 50; 24th Div WD, 2 Aug 50. The 24th Division received the Eighth Army Directive, dated 1 August 1950, at 020230.  24th Div WD, 3-4 Aug 50; 21st Inf WD, 2-3 Aug 50; 24th Div G-3 Jnl, Msg 483, 022330 Aug 50; EUSAK WD, G-3 Jnl, 3 Aug 50.  19th Inf WD, 22 Jul-4 Aug 50; Ibid., 22 Jul-25 Aug 50, Logistics sec.  Ltr, Gay to author, and attached notes, 24 Aug 50; EUSAK WD, G-3 Jnl, 3 Aug 50, Msg from 1st Cav Div.  Ltr, Gay to author, 24 Aug 50; EUSAK WD, G-3 Jnl, 3 Aug 50; Ibid., POR 66, 3 Aug 50. By the end of July 1950, the South Korean government had established fifty-eight refugee camps, most of them in the Pusan- Taegu area, to care for the homeless people.  EUSAK WD, Opn Directive in G-3 an., 1 Aug 50; Ibid., POR 61, 2 Aug 50; GHQ UNC G-3 Opn Rpts 38 and 39, 1-2 Aug 50; GHQ UNC, Telecon TT3619. 3 Aug 50.  EUSAK WD, G-3 Jnl, Msg at 301850 Jul 50; Ibid., G-3 Sec, Msg at 020845 Aug 50; Ibid., G-3 Sec, 2 Aug 50.  24th Div WD, G-2 Jnl, 2-5 Aug 50, entry 232, 4 Aug 50.  EUSAK WD, 4 Aug 50, Plan for Relief of 24th Inf Div.  Memo, Hickey for CofS FEC, 7 Aug 50; sub: Report on Visit to Korea.  25th Div WD, 4 Aug 50; Ibid., Summ, Aug 50; 35th Inf Unit Hist, 3-4 Aug 50; 27th Inf WD, 3d Bn, 27th Inf, Hist Rpt, Aug 50; EUSAK Opn Directive 031830 Aug 50. The 25th Division now had the normal 9 battalions in its 3 regiments. An Eighth Army radio message on 3 August ordered the 1st and 3d Battalions, 29th Infantry, attached to the 25th Division. The division, in turn, on 6 August attached the 1st Battalion to the 35th Infantry and the next day attached the 3d Battalion to the 27th Regiment, as their third battalions.  EUSAK WD, G-3 Sec, 3 Aug 50, Msg at 031130; Ibid., 4 Aug 50, Plan for Relief of 24th Inf Div.  1st Cav Div WD, G-2 Narr Rpt, Aug 50; EUSAK WD, POR 66, 3 Aug 50.  Guderian, Panzer Leader, p. 265.  EUSAK WD, POR 64, 3 Aug 50; GHQ UNC Sitrep, 5 Aug 50.  ATIS Res Supp Interrog Rpts, Issues 99, 94, 104, 100, 96, 3, and 4; GHQ UNC Telecon TT3619, 3 Aug 50; TT3623, 4 Aug 50; TT3630, 7 Aug 50. GHQ UNC Sitrep, 6 Aug 50, and TT3623 have the N.K. 2d Division opposite the ROK 1st Division. Actually, the enemy 2d Division was in a rest area behind the line. The N.K. 1st Division entered the Perimeter battle 8 August, after resting at Hamch'ang several days and taking in several thousand replacements.  GHQ FEC, History of the N.K. Army, 31 Jul 52, pp. 41-42.  "Air War in Korea," Air University Quarterly Review, IV, No. 2 (Fall, 1950), 19-39. Fourteen fighter-bomber groups supported Bradley's 28 divisions; at the end of July 1950, 8 fighter-bomber groups supported the 3 American and 5 ROK divisions in Korea.  GHQ FEC Sitrep, 12-14 Jul 50: New York Times, July 23, 1950. The 92d Bombardment Group was at Yokota in Japan; the 2d, at Kadena on Okinawa.  GHQ UNC G-3 Opn Rpt Nr 33, 27 Jul 50; Nr 35, 29 Jul, and Nr 37, 31 Jul 50; New York Times, Jul 28, 1950.  GHQ FEC Sitrep, 22 Jul 50.  USAF Hist Study 71, pp. 35-37.  "Air War in Korea," op. cit., p. 21.  Ibid.; Karig, et al., Battle Report: The War in Korea, p. 104: New York Times, July 23, 1950. The Boxer also brought to the Far East 25 other planes, 1,100 Army and Air Force personnel, 190,000 gallons of aviation gasoline, 16,000 gallons of lubricating oil, and a very large cargo of shells, bombs, and other ammunition.  FEAF Opns Hist, vol. 1, 25 Jun-1 Nov 50, pp. 89-90.  Interv, author with Maj Gen George L. Eberle, Jan 54. Eberle was GHQ UNC G-4.  GHQ UNC Sitrep, 31 Jul 50; GHQ UNC G-3 Opn Rpt, 1-2 Aug 50; Schnabel, FEC, GHQ Support and Participation in Korean War, ch. iii, p. 23; 24th Div G-3 Jnl, 29 Jul-6 Aug 50, entry 420, 011825.  2d Div WD, 8 Jul-31 Aug 50, G-2 Hist Sec, pp. 14, 28; EUSAK WD, G-3 Sec, 30 Jul and 2 Aug 50.  2d Div WD, 8 Jul-31 Aug 50, G-2 Hist Sec, p. 28.  1st Prov Mar Brig Special Act Rpt (hereafter cited as SAR), 2 Aug-6 Sep 5, pp. 1-4; 5th Mar Regt SAR, 2 Aug-6 Sep 50; 1st Bn, 5th Mar, SAR, Aug 50, p. 1; EUSAK WD, G-4 Stf Sec, 3 Aug 50; Ibid., POR 64, 3 Aug 50; GHQ UNC G-3 Opn Rpt, 3 Aug 50. Lynn Montross and Capt. Nicholas A. Canzona, USMC, U.S. Marine Operations in Korea, 1950-1953, vol. 1, The Pusan Perimeter (Washington: Historical Branch, G-3, Headquarters, U.S. Marine Corps, 1954), pp. 65-89. This and succeeding volumes give a detailed account of the marines' part in the Korean War. Canzona, a participant in the Marine operations in Korea, was a member of the Marine brigade and subsequently of the 1st Marine Division.  GHQ UNC G-3 Opn Rpt 41, 4 Aug 50; EUSAK GO 189, par. 1, 0001, 7 Aug 50, GHQ UNC G-3 Opn Rpt 37, 31 Jul 50.  EUSAK WD, 31 Jul 50, Memo for Col Conley, sub: Projected Replacement Status; Ibid., G-1 Stf Sec. Replacement quota for August was 1,900 officers, 9,500 enlisted men; for September, 1,500 officers, 1,500 enlisted men; and for October, 1,200 officers, 16,000 enlisted men.  Pusan Logistical Command Activities Rpt, Trans Sec, Jul 50; Mossman and Middleton, Logistical Problems and Their Solution, EUSAK.  GHQ UNC G-3 Opn Rpt 37, 31 Jul 50; "Air War in Korea," op. cit., p. 21.  GHQ FEC Sitrep, 20 Jul 50.  Ibid., 23 Jul 50; EUSAK WD, Summ, 13-31 Jul 50, 25 Jul; Ibid., G-4 Stf Sec Rpt, 25 Jul 50.  Pusan Log Comd, Activities Rpt, Trans Sec, Jul 50; Ibid., HQ, Plat Ldrs' Class, (B) (Provisional), Memo 1, 18 Jul 50.  Ibid., Trans Sec and Table V, Jul 50.  GHQ FEC Ann Narr Hist Rpt, 1 Jan-31 Oct 50, p. 47; EUSAK WD, G-3 Sec, 1 Aug 50, Ltr of Instr 1, Office of Coordinator, Lines of Comm.  Mossman and Middleton, op. cit., pp. 8, 12.  GHQ FEC Ann Narr Hist Rpt. 1 Jan-31 Oct 50, p. 39; GHQ FEC Sitrep 24 Jul 50.  Training Bul 3, Off, Chief of Army Field Forces, 28 Nov 50; Capt Robert K. Sawyer, Notes for author, 1 Oct 52.  Typical daily battle casualty reports of this period: 30 Jul-Army, 617, including 20 KIA, 126 WIA, 417 MIA; Navy, 0; Air Force, 1 (MIA); 31 Jul-Army, 328 (20 KIA, 181 WIA, 127 MIA); Navy, 0; Air Force, 3 (1 WIA, 2 MIA). GHQ UNC G-3 Rpts 37-39, 31 Jul-2 Aug 50.  DA Battle Casualties of the Army, Final Rpt 30 Sep 54, and CTM, 31 May 52. Casualties for the last half of July totaled 4,754, including 1,265 KIA, 2,345 WIA, 971 MIA, and 173 reported captured. Eighth Army gives the total as 5,482, including 272 KIA, 1,857 WIA, and 3,353 MIA, presumably covering the period of 13-31 July. See EUSAK WD, Summ, 13-31 Jul 50. The discrepancies between Eighth Army figures and final TAGO figures are explained in part by the fact that casualty reporting in the field is governed by regulations which provide that, unless the body is recovered or the person is actually reported in the hands of the medics, the man is reported missing in action. When additional information is received, TAGO's official casualty records are revised, and the result is reduced figures for those missing and increased figures for those killed, wounded, or captured.  EUSAK WD, 4 Aug 50, CofS Slip Note 1, Plan for Relief of 24th Inf Div.  GHQ UNC G-3 Rpts 39, 2 Aug 50, and 41, 4 Aug 50.  New York Times, July 30, 1950; DA Wkly Intel Rpt 76, 4 Aug 50.  The estimates of both enemy losses and strength are based on enemy materials-captured documents and interrogation reports. These, taken as a body, are believed to be more reliable than estimates prepared by U.N. authorities as the battle progressed, which could be little better than guesswork. This is particularly true of the period under discussion as the enemy held the battlefield during the U.N. withdrawal movements to the Pusan Perimeter and there seldom was an opportunity to count his dead. The replacements received in the enemy combat units, as reported in prisoner interrogations, have been included in the strength figure. See ATIS Res Supp Interrog Rpts, Issue 3 (N.K. 1st Div), p. 33: Ibid., Issue 94 (N.K. 2d Div); Ibid., Issue 96 (N.K. 3d Div), p. 33; Ibid., Issue 94 (N.K. 4th Div), p. 48; Ibid., Issue 96 (N.K. 5th Div), p. 42; Ibid., Issue 100 (N.K. 6th Div), pp. 38-39; Ibid., Issue 99 (N.K. 12th Div), pp. 44-46; Ibid., Issue 104 (N.K. 13th Div), p. 60; Ibid., Issue 3 (N.K. 15th Div), p. 42; Ibid., Issue 4 (105th Armed Div); 27th Inf WD, PW Interrog Rpt 10; 1st Prov Mar Brig SAR, II.  ATIS Res Supp Interrog Rpts, Issue 4 (105th Armd Div); 24th Div G-2 Jnl, 2-5 Aug 50, entry 256, 041010.  ATIS Res Supp Interrog Rpts, Issue 106 (N.K. Arty), pp. 23, 66. This figure probably includes the 122-mm. howitzers. The standard North Korean division artillery included twenty-four 76-mm. guns and twelve 122-mm. howitzers. Most of the Russian-supplied artillery ammunition used by the North Koreans was four or five years old and verdigris deposits coated the shell casings. There were many misfires and duds. Until about October 1950, the North Koreans used only two types of artillery ammunition, high explosive and armor piercing. The shell had a point detonating fuze to which a nose cap could be attached to give a slightly delayed burst.  GHQ UNC Sitrep, 4 Aug 50. The 24th Division figures include the 5th Regimental Combat Team and the 1st and 3d Battalions of the 28th Infantry. These units were attached to the 25th Division about the time the Far East Command issued the 4 August situation report.  GHQ UNC G-3 Opn Rpt 41, 4 Aug 50; Ibid., Sitrep to DA, 5 Aug 50. The ROK Army transferred about 14,000 of the approximately 82,000 troops listed in the estimate to labor units, so the over-all troop strength of U.N. forces would fall proportionately. This would not affect the combat forces figures.  New York Times, July 26 and 30, 1950.