At the outbreak of the Korean War, the United States Air Force (USAF) had >1000 aircraft in the Pacific region.
Immediately mustered against the North Korean invasion were F-80 Shooting Stars, F-82 Twin Mustangs, B-26 Invaders and B-29 Superfortresses. USAF aircraft were well-equipped and flew from many bases in Japan—out of North Korean reach.

Additionally, air squadrons from Great Britain and Australia provided support for ground operations.

At the onset of the Korean War the Republic of Korea Air Force had 1,800 personnel but only 22 aircraft.

The North Korean People’s Air Force (KPAF) had 2000 personnel and 132 aircraft.
From June 25 to July 20, 1950 North Korean aircraft waged a battle for air supremacy over South Korea.
In the initial phase of the war, North Korean aircraft held air superiority over South Korea.
However, several engagements over Seoul and Taejon ultimately ended in the destruction of the small KPAF.
Despite unsuccessful UN ground action in the early stage of the Korean War, the air battle was successful for UN forces.

After destruction of the small KPAF, the UN air force concentrated attacks on North Korean ground forces, inflicting heavy casualties. In addition, UN bombing of North Korean armor, supplies and ports, greatly hampered enemy efforts to penetrate the Pusan Perimeter.
U.N. bombing continued relatively unhindered for six months of the war ~ until the ominous appearance of the Soviet-built MiG-15 fighter (presumably flying out of Manchuria).

At the top of my list of great war flicks, next to “Paths of Glory” is “The Bridges at Toko-Ri”. When I first saw it (and loved it) at age 12, I missed the underlying anti-war theme. William Holden’s brilliant performance of a man forced to fight a war he couldn’t understand and dying alone in a ditch thousands of miles from his family, tells the story of 10,000’s of Americans who never came home from questionable wars in the last 70 years.
https://youtu.be/uZ1f0OA752w
The book by James Michener was likewise a somber account of this dangerous but dreary air war.
Writer James A. Michener wrote the story after spending time aboard the USS Essex. One of the pilots aboard the Essex at the time was Neil Armstrong. It is not known for certain whether any of the characters in the book or movie were based on Armstrong.