<p>MacArthur's planners for the Inchon landing wanted massive air support following the patterns established five and six years earlier . The aim of Interdiction Campaign No. 2, scheduled to begin on 9 September, was to ready the objective area. Targets were bridges again, north of a line between Pyongyang and Wonsan; they were Bomber Command's, while Fifth AF gave close support to the landing. The campaign lasted into late September, and went as planned except that the ground troops moved faster than expected. The interdiction moved north, to stay ahead of their advance.
</p>
<p>Targets for the third campaign were bridges on both coasts. Bomber Command destroyed many of them, cutting off the retreating NKA forces, but also hampering the advance of the UN armies to some extent.
</p>
<p>The fourth campaign was long, bitter and best in terms of results. Planned before the Chinese entered the war, it was quickly changed to strike at their supply lines during their rapid advance southward. That objective was temporarily cancelled by MacArthur's request for heavy air strikes against troop concentrations, and the towns and villages hiding or supplying the Chinese and North Korean armies. Little interdiction was accomplished during the first month.
</p>
<p>After the first week of January 1951, all available aircraft were pressed into service. The retreat of the Eighth Army was not turned into a rout because of the close air support given by tireless airmen. USAF air was so active that the Chinese armies could only move by night. Their drive, under the pressure of constant air attacks and the damage of interdiction, began to slow. Their logistics system gave way. Foraging became a necessity. Ammunition and rifles had to be captured instead of being supplied. Reinforcements took as long as four months to reach the front from the Yalu crossings. It was too much to stand, and the Chinese were forced to negotiations.
