The Cold War started with the USA use of nuclear weapons on Japan.

Was the only reason Russia did not receive the wrath of the USA nuclear capacity because it was needed as an ally in WWII? Russia wasn't going to ask a second time. It was going to prepare for a new world of unconventional war potential by the USA.

How far would a 'ally in need' actually take the relationship? Was Russia to be another Japan?

...For their part, (click here) the Soviets resented the Americans’ decades-long refusal to treat the USSR as a legitimate part of the international community as well as their delayed entry into World War II, which resulted in the deaths of tens of millions of Russians. After the war ended, these grievances ripened into an overwhelming sense of mutual distrust and enmity. Postwar Soviet expansionism in Eastern Europe fueled many Americans’ fears of a Russian plan to control the world. Meanwhile, the USSR came to resent what they perceived as American officials’ bellicose rhetoric, arms buildup and interventionist approach to international relations. In such a hostile atmosphere, no single party was entirely to blame for the Cold War; in fact, some historians believe it was inevitable....