Historians say it takes 50 years to fully understand any conflict, and yet, even after a full half-century, Korean War accounts still are marred by a huge gap. They generally do not explain the July 1950 collapse of North Korea’s invasion.
Communist North Korea launched its offensive south from the 38th parallel on June 25, 1950. Seoul, South Korea’s capital, fell in a mere four days, on June 28. Trying to slow down the communist advance, South Korea prematurely destroyed bridges over the Han River, trapping most of the 95,000 retreating South Korean soldiers. By July 1, only 22,000 South Korean troops were still in action.
Thus, after Week 1 of the war, the Republic of Korea’s situation seemed hopeless. North Korean forces had crossed the Han and were poised for the knockout. Three depleted ROK divisions faced nine crack communist divisions—about 90,000 troops led by 150 T-34 tanks. The T-34s were impervious to ROK antitank weapons.
From the Han, it is only 250 miles to the town of Pusan, the capture of which would have sealed off the peninsula, forcing the United States to contemplate a bloody, D-Day type amphibious invasion. Seemingly, fast-charging communist forces had a clear path to reach it in a few weeks or even days.
North Korea, of course, didn’t get to Pusan in July—or ever. It is a failure that has never been adequately explained in any public way. North Korea has refused to release authentic historical data. Western reporters weren’t on the scene to provide firsthand accounts.
However, USAF operational records and a few other sources are available, so at least a one-sided outline of the events of July 1950 can be presented. What these accounts show is what may well have been the Air Force’s greatest one-month achievement of the entire Cold War period.
Simply put, they suggest that the Air Force saved South Korea by harassing and greatly slowing the North’s advance. Roy E. Appleman, an Army Korean War historian, concluded that North Korea’s July failure to conquer the peninsula gave UN ground forces time to arrive and hold the Pusan Perimeter. With that, the tide turned.
USAF’s Far East Air Forces went into action within days of the surprise attack. By July 1, the end of the first week, FEAF was the most effective resisting force, and this continued throughout the month. The importance of airpower in the outcome of the war can be seen in FEAF’s week-by-week action.
July 2-8: On July 4, communist forces headed south toward Osan, Taejon, and Taegu on the main route to Pusan (see map). Other North Korean penetrations swept over South Korea’s mountain passes and down Korea’s east coast with little resistance.
USAF B-26s flew close air support for ROK forces. F-80s and F-51s, flying at maximum range from Japan, provided air cover and struck ground targets. Fighters spotted huge North Korean vehicle convoys stopped behind a destroyed bridge 15 miles south of Osan. For three days, B-26s and F-80s hammered the columns, claiming 197 trucks and 44 tanks destroyed. Some thought these claims were exaggerated, but one Army veteran said, “There were considerable losses.”
Communist forces evidently had not been trained to meet the hazards of opposing air strikes. Noted one air commander, “We would time and time again find convoys of trucks that were bumper to bumper against a bridge that had been knocked out, and we’d go in to strafe them, and every man in the truck would stand up where he was and start firing his rifle at us.”
The US Navy contributed to the air war and controlled the seas for transporting troops and supplies to South Korea. On July 2, a Navy cruiser and two British ships sank two North Korean torpedo boats and some small freighters. The next day, Task Force 77, with the carriers USS Valley Forge and Royal Navy Triumph, began interdiction and counterair strikes against Pyongyang and other targets in North Korea.
Navy forces, unable to communicate well with the Army and Air Force, asked for exclusive use of their own airspace in North Korea. Alone there, they flew air superiority missions and struck bridges and other interdiction targets.
In early July, the ROK Army located two relatively intact divisions and many stragglers. Adding these to its surviving forces, the ROK Army now totaled 54,000. However, Appleman observed, “This left 44,000 completely gone in the first week of war.”
Also in the war’s second week, Task Force Smith, a 500-man advance contingent of the US Army’s 24th Infantry Division (ID), got to the battlefield from Japan. North of Osan on July 5, communist forces battered them in little over an hour. Task Force Smith “had no hope of stopping the [North Koreans],” concluded one historian. For unknown reasons, communist forces halted after advancing 70 miles in four days and capturing Osan and Ch’onan. Otherwise they might have smashed the entire 24th ID and opened the route straight to Pusan.
July 9-15: Committing small 24th ID units piecemeal against the North Korean juggernaut was disastrous, but USAF air strikes intensified, and, on July 12, long-range B-29 bombers began pounding targets far from the battlefield.
Gen. O.P. Weyland, a later FEAF commander, wrote that communist forces soon began to move supplies and troops by night, so FEAF adopted an intensive and very effective B-26 night interdiction campaign. Though small in relation to overall air efforts, this helped greatly to reduce North Korea’s daily supply flow “from a 206-ton average in early July to a mere 21.5 tons during the … Pusan Perimeter defense.”
Communist forces advanced only 30 miles in Week 3. They mysteriously divided their forces for a double envelopment around the main route. A left probe swung over to the east coast. On the right, unseen for almost two weeks, a “Ghost Division” headed into the far southwest center of Korea.
July 16-22: The North Korean Army shattered the 24th ID and captured its commander, Maj. Gen. William F. Dean, as well as the key city of Taejon. In 17 days, the 24th had suffered more than 30 percent casualties.
However, ROK divisions were strengthening, and the US 25th Infantry Division entered the fight. US troops began receiving 3.5-inch rocket launchers to kill T-34s. And North Korea’s Air Force stopped combat flying. “The air battle was short and sweet,” observed Lt. Gen. George E. Stratemeyer, FEAF commander. Communist forces advanced only 25 miles in Week 4.
July 23-29: The ROK Army, regrowing rapidly from vigorous recruiting and returning stragglers, now had five divisions. America’s third division in Korea, 1st Cavalry, began fighting in this fifth week.
It was clear, however, that air attack was taking a toll against northern forces. North Korea again advanced a mere 25 miles. Prisoners from one North Korean division complained: “Air attacks alone killed 600 North Korean soldiers. … Much of the artillery had been sent back [because] … NK supply could not get ammunition to the guns. … Eleven of the division’s 30 tanks had been lost, and … the division commander had been killed.”
The eastern probe of North Korea’s double envelopment was checked by the ROK Army at the northern Naktong River. In the southwest, the “Ghost Division” moved ahead stealthily toward Pusan. Finally detected, it was stopped mainly by the reconstituted 24th ID.
By Aug. 1, it was clear that the North Korean advance had stalled and would fall short of its goal. In some 32 days, the North Koreans had advanced 165 miles but at increasing cost. In week two, communist forces were advancing at a rate of 17 miles per day. By week six, they were down to two miles per day. And there were still 85 miles to go.
Through July, FEAF flew 4,300 close support and 2,550 interdiction missions. It was clear that these airstrikes were taking a vicious toll on communist forces. The main invasion route was littered with destroyed highway and railway bridges. Communist troop losses, it was learned later, had been 58,000—almost twice what Gen. Douglas MacArthur’s headquarters estimated at the time. T-34 tank losses were well over 100; despite reinforcements, only 40 were left.
On Aug. 3, in the war’s sixth week, US-led allied forces established the Pusan Perimeter along the Naktong River. By then, UN forces totaled 92,000, with five ROK and the three US divisions plus varied allied units and the newly arrived 2nd ID and 1st Provisional Marine Brigade. Though believed to be superior at the time, North Korea’s 11 divisions totaled only 72,000.
As recounted often by historians, Eighth Army held that line through six weeks of ferocious ground battles until, on Sept. 15, MacArthur’s Inch’on landing broke North Korea’s back.
The Eighth Army commander, Gen. Walton H. Walker, deemed airpower a critical factor. “I will gladly lay my cards right on the table and state that, if it had not been for the air support that we received from the Fifth Air Force, we would not have been able to stay in Korea,” said Walker.
Walker was echoed by Gen. Matthew B. Ridgway, Eighth Army commander after Walker’s death in December 1950. He wrote: “As for the airmen, without them, the war would have been over in 60 days, with all Korea in Communist hands.”
Even more impressive was what American troops saw when they broke out after the Inch’on landing. Leaving the Pusan Perimeter and traveling north more than 100 miles toward Seoul, one soldier wrote home: “I have never seen so many wrecked vehicles and tanks. The sides of the roads were littered with them. … Counted 65 knocked-out North Korean tanks. The Air Corps did just about all of it. Outside Taejon, I saw 13 tanks on one hill, all dug in and concealed, that had been knocked out. The Air Corps uses napalm (gasoline) on all and just burns them out. … The Air Corps has been the key figure.”
Ground-oriented historians had divergent views. One Korean War Army veteran felt that “while FEAF could quickly wipe out the small [North Korean] air forces, it immediately became obvious that American airpower alone could not seriously affect the outcome on the ground. The [North Koreans] took their losses and came on.” However, he later added that without air and sea superiority “during the dark days of midsummer 1950, the United Nations presence on the Korean Peninsula would have ended.”
One critical Army study of air interdiction in the Korean War looked only at what happened after July, after the US Army had arrived in force. Noting that while air interdiction “made a worthwhile contribution” and “was particularly helpful during the early months,” the study concluded it “was not a decisive factor in shaping the course of the war.”
Out of Sight …
A USAF historian remarked that “interdiction efforts in Korea were never fully appreciated by the ground forces, who seemed to believe that air attacks they could not see were of little value in containing or stopping the enemy.”
After the demise of the Soviet Union, fresh facts from Moscow’s files shed new light on USAF’s July 1950 achievements. Former Soviet Foreign Ministry and Chinese archives became available. Among records of diplomatic meetings and correspondence are references to a “Pre-emptive Strike Operational Plan” for the attack on South Korea. Prepared by the Soviets, it was translated and used by communist forces.
The strike plan called for North Korea to advance nine to 12 miles (15 to 20 kilometers) per day and end the war in 22 to 27 days. Thus, North Korea intended to defeat South Korea by the fourth week. Clearly, July 1950 was the Korean War’s critical month.
Certainly communist forces felt extreme pressure to act urgently after capturing Seoul, especially when America responded so quickly. Only USAF air strikes can explain North Korea’s five-day halt before starting south from the Han.
Also, to knock out South Korea in four weeks, communist forces had to get within striking distance of Pusan by the end of Week 3. Instead, they were only halfway there, visibly slowing, and moving only by night.
Unforeseen in North Korea’s strike plan, FEAF interrupted their logistics and caused massive casualties. The invaders’ “double envelopment” maneuver now can be seen as a desperate attempt to divide, spread out, and maybe even hide to avoid constant USAF air attack.
Allied ground forces still were too weak to slow North Korea without air support. FEAF’s singular, sometimes almost solitary role in July is obvious. By Week 4, when North Korea had intended to end the war, America had only two divisions in combat, amounting to half the ROK’s size and a third of North Korea’s. And the ROK Army itself was staggered by retraining, re-equipping, and reorganizing tasks. Despite Eighth Army’s reinforcements by week six, it’s a marvel they could establish the Pusan Perimeter and hold it for six bloody weeks until the Inch’on landing.
Indisputably, those ground forces accomplished heroic and magnificent deeds.
Still, timing is all-important in warfare. North Korea knew that, so they prepared a one-shot, quick-results attack plan. Such a plan existed and was used. Fortunately, in July 1950, USAF was on hand to thwart that plan, thereby saving South Korea.
Kenneth Moll graduated from West Point 18 days before the Korean War began. A fighter pilot, he flew F-80s in Korea and T-39s in Vietnam. Later a Pentagon planner and think tank president, he’s now a Cold War historian. This is his fourth article for Air Force Magazine.