 Complete the following phrase:  The next day, 25 November 1950, Walkers Eighth Army was attacked by the Chinese Army and soon the UN forces were in retreat. MacArthur provided the chief of staff, General J. Lawton Collins with a series of nine successive withdrawal lines. On 23 December, Walker was killed when his jeep collided with a truck, and was replaced by Lieutet General Matthew Ridgway, whom MacArthur had selected in case of such an eventuality. Ridgway noted that MacArthurs prestige, which had gained an extraordinary luster after 