War in Korea and Indochina } 77
Korea in October and the onset of heavy fighting led Stalin to modify his pos-
ition and agree to provide air cover. On November 1, 1950, about a week after
the CPV engaged US/UN forces, Stalin finally permitted Soviet warplanes,
manned by Soviet pilots but with Soviet markings painted over, to cross the
Yalu and engage US planes operating over North Korea. Still, Soviet air sup-
port was tardy and inadequate, and a source of Chinese dissatisfaction with
Stalin’s policies.
On March 1, 1951 Mao sent Stalin a cable emphasizing the urgent need for
stronger air protection of CPV supply lines and requesting Soviet assistance
in this regard. The Soviet leader agreed to deploy two air force divisions,
three anti-aircraft divisions, and 6,000 trucks to Korea. Soviet assistance,
along with road, railway, and bridge construction efforts by PLA engineers,
improved the CPV supply situation. Throughout the war and for many years
thereafter, the participation of Soviet air forces in combat with the United
States over North Korea was kept top secret by both Beijing and Moscow.
Although US intelligence soon determined the actual situation, it was hotly
denied by Beijing and Moscow. Even after the collapse of the Sino-Soviet alli-
ance circa 1960, Beijing and Moscow felt it best to keep secret their joint air
war against the United States. Not until the post-Soviet release of Korean War
documents were the inner workings of this clandestine Soviet-Chinese air
war against the United States revealed.
The CPV responded to US air bombardment by building numerous cam-
ouflaged refuges for trucks in caves or gullies. A system of aircraft spotters
was organized atop hills to give early warning of approaching aircraft. Once
alerted, CPV trucks would quickly seek shelter. Broken-down trucks and fake
bunkers were left just visible enough to attract US bombs. CPV command-
ers also adapted by ordering some percentage more than the amounts actu-
ally needed. Thus perhaps 20 percent more than the amount actually needed
would be requisitioned, so that if 20 percent was lost en route, requirements
would still be met. CPV forces adapted to heavy US air and artillery bom-
bardment of front-line positions by digging deep tunnels and bunkers be-
hind those positions. Main defense forces would shelter in these more
protected rear positions until the US bombardment lifted, typically shortly
before the US assault began, and then rush into front-line positions just be-
fore advancing US forces closed on the CPV front line. Chinese forces also
waged “see-saw battles” in which they would seize US positions, withdraw
when counterattacked, but then quickly counterattack themselves before the
exhausted enemy had time to rest or consolidate their defenses. On other
occasions, CPV forces would simulate a forced withdrawal of up to thirty
kilometers, and then turn and defend strongly as US/UN forces attempted to
follow through on what they supposed had been their “breakthrough.”
Chinese scholar Shu Guang Zhang stresses that Mao fundamentally mis-
understood the nature of modern warfare as experienced by Chinese forces