Before the birth of the Soviet Union, as such, after the Russian Revolution of 1917, the United States, and the country that was always known as Russia, had friendly relations that were reinforced through their alliance prior to the Revolution. From 1917 onward, because of the coming into power of Communism, a new system of government that totally opposed the U.S belief in democracy, the right to personal property and the free market, resentment and suspicion grew between the two nations. However, after WWI and during WWII, both the U.S and Russia were forced by need and circumstances to collaborate with each other, especially in WWII. The problem arose because of the tug-of-war that ensued between the two nations, who initally began competing with each other to prove to the world which system of government was the correct one. This confrontation became absolutely evident before the end of WWII, on July 16, 1945, with the release of the nuclear bomb on the towns of Hiroshima and Nagasaki. The reason? Because with the appearance of this power on the hands of the U.S, the now named Soviet Union lost the race to become the only superpower in the globe. In the end, that was the issue that forced enmity between the two nations; the differences of system of government and the thirst to prove their superiority over the other by becoming the greatest superpower.
After WWII, and especially after the release of the nuclear bomb, the race for the upper hand between the U.S and USSR became almost frantic. Constant conflicts led into what is historically known as the Cold War (1947-1991) and this period of history became riddled with fear. Division in the world also took place. There were the block of nations that supported the U.S and those that supported the USSR, especially Communism. Events as serious as espionage cases between the two countries, the building of the Berlin Wall, which literally tore the East from the West (Communism vs Capitalism and Democracy), conflicts within the nations themselves over supposed infiltration of either system to the other, the Korean and Vietnam War, the Chinese Revolution and the serious confrontation that took place at the Bay of Pigs (1961), in Cuba, when Fidel Castro took control of the country and installed a Communist government under the support of the USSR, who also wished to settle a military base with nuclear missiles in the Cuban nation, which led to the Cuban Missile Crisis of 1962 and almost to a third world war, are just a few of the examples that come to show how serious the race between these two powerful nations became and the dire consequences it had on the entire planet.
"The spread of religious ideals" was not a significant factor in the Aztecs expansion for their empire, since their primary goal was to gain more territory for population expansion and to gain more resources.
