Why did the world war 2 alliance between the USA and the USSR dissolve?

Also, do you have any good sources - books - on this topic? I'm writing an article on this.Why did the world war 2 alliance between the USA and the USSR dissolve?
You make it sound like that happened during the war... it didn't of course. After the war, the USSR refused to give back control of the east European countries they liberated from Nazi Germany %26amp; instead put up communist regimes. They even held on to east Germany %26amp; made it into a communist satellite country; Germany would remain separated into two nation %26amp; Europe would be divided by the metaphorical "Iron Curtain" with east Europe being mostly communist states. The difference in political ideology between the USSR %26amp; the USA was so great that it was inevitable that they would view each other as enemies. The western democratic nations would form the North Atlantic Treaty Organization (NATO) as a new alliance against communist countries %26amp; The communist nations would form the Warsaw Pact as a mutual alliance against the western NATO countries.Why did the world war 2 alliance between the USA and the USSR dissolve?
The USA/USSR alliance of World War 2 was temporary and both parties realized this. Relations started breaking down at the end of the war over the Soviets actions in Poland, Hungary and Czechoslovakia; the USSR interfering with the process of creating the post-war governments. The break was final by 1948 when the USSR blockaded the western sectors of Berlin. Winston Churchill's "iron curtain" speech from that time is a good summary of western reactions to Soviet behavior.