Earth Judicar
Banned
I think you are oversimplifying the US's geopolitical ideology somewhat. During its early history the US remained aloof from European conflicts as Washington said "no entangling alliances". By the end of the 19th century you had politicians making arguments for conquering the Phillipines based on economics and strategic location alone without any moral appeal.I find it's less the Soviets as a sort of evil omnicidal entity and more that the two countries just have such a virulently opposed outlook on the world that they were bound to clash over it's fate in the post-war. The Soviets had the inheritance of Tsarist Russia's old geopolitical position that propelled it's expansion coupled with the ideological doctrine of communism, which held that true cooperation with non-Communist states was impossible. This gave them a foreign policy based on brutal realpolitik infused with the strange "internationalist-nationalist" that Leninist and Stalinist thought expounded: the capitalists would invariably seek to destroy the Soviet Union, as the bastion of the workers revolution whose destruction would mean a major setback for said revolution the security of the USSR must be held above everything else, security was a zero-sum game which could only come to the Soviet Union at the expense of others, foreign policy can only be based on objective factors (relative military-industrial strength and situation) between countries, the exposed borders of the USSR can only be secured by buffers, etc. etc. Morality simply doesn't enter into it. Even all the other contenders for power prior too and after Stalin, Khruschev included, bought into these ideas to some degree or another.
For it's part, the US's ideological view was influenced by it's own geopolitical position and internal history, which combined a homeland that could not actually be challenged with great prosperity and great regard for individual rights. This resulted in an highly individualistic and moralistic view of international relations which tended to view foreign policy through a prism of "free and not free" and "good vs evil" that was uncomfortable with focusing, or even acknowledging, large-scale movements and instead focused on national leaders to make an ally or enemy out of, a view which believed that security and global peace could be based on cooperation of national leaders working together to create world orders and arbitrate disputes. This was a policy that frequently clashed with the uncomfortable reality of a global or regional situation, as the entire history of US foreign policy from WW1 on can attest, but it even in it's most realpolitik moments the US sought to infuse it into how it conducted itself in the world... even if it was flagrantly immoral actions in the pursuit of these moral goals (remember the saying about the path to hell?).
Such viewpoints in the two most powerful military superpowers was bound to create too much friction for actual cooperation to be possible.
The whole post war history of the US and quite famously the machinations of the CIA show the US government did indeed look at things from a more cynical and imperial angle.
Thing is as Zbigniew Brezezinki noted empire is hard to sell to a democratic populace and so must be coated using appeals to morality and security.
As for the Soviet Union-I think by the fifties it was more interested in maintaining the status quo at least in Europe. If by some luck Western Europe experienced communist revolutions or unrest post war there is no guarantee that the USSR would benefit. After all what if France went Trotskyist or something? Better to maintain an uneasy status quo while seeking to check the Americans in the third world.