The usa has never trusted Russia so i am not sure why they fell into bed with a commie China. I blame the start of this on Nixon bowing to mao
On February 21, 1972, Chinese leader Mao Zedong and US Nixon met to normalize relations between their two countries. Their meeting in Beijing was brief but it set the scene for what has become the most important economic relationship in the world.
Why we thought one would be better than the other
Never trusted Russia? They were allies all through World War I until Russia exited the war in 1918 to deal with the revolution going on at home. Then, once World War I was over, the US and countries that are now members of NATO invaded Russia to intervene (or rather interfere) in their civil war. When the Bolsheviks won, the US and these Western countries withdrew, and this whole 'intervention' pretty much started the Cold War. Russia has had every right —not to trust— the United States. Hell, the United States even changed terms of agreements made after the fact and even rearmed Germany, despite the fact that they along with Britain, France and the Soviets agreed that Germany would never be allowed to do so. This prompted the Soviet Union in 1954 to apply for membership in NATO, specifically —because— they didn't want another war.