The USSR and the USA are both to blame. (my opinion)

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Hard to say. The US leadership had been rabidly anti-communist for decades, afraid of communist take over of american business, and the subsequent loss of profit. Red Scares were common. But the extreme paranoia of Joseph Stalin and his unmatched butchery gave the anticommunists a true rational reason to fear Stalin. Stalin's behavior in the Berlin crisis certainly didn't help matters.
The russians feared the American's atomic bomb. And they feared a rebuilt Germany. Germany had attacked them twice in 25 years. The americans and the rest of the west feared Russia's tank armies. The American move to encirle russia plus provocative flights, made the Russians even more suspicious of Western motives.

http://answers.yahoo.com/question/index?...


The question as to whether the United States or the USSR was more to blame for starting the Cold War has produced heated debate among twentieth-century historians. For years, most historians placed blame squarely on Soviet shoulders and helped perpetuate the notion that Americans wanted merely to expand freedom and democracy. More recent historians, however, have accused President Truman of inciting the Cold War with his acerbic language and public characterization of the Soviet Union as the greatest threat to the free world. Although conflict between the two powers was arguably inevitable, the escalation into a full “hot” war and the attendant threat of nuclear annihilation might have been avoidable.

http://www.sparknotes.com/history/americ...



This is interesting (please don’t just read the top)

http://www.johndclare.net/cold_war1_answ...

The USA never wanted any cold war. Democracies do not like war of any type.
The Russian Communists wanted to grab power over as much as they could. The USA had to meet this threat and keep as many people from losing their freedom as they could.

There are a lot of socialists and socialist sympathizers around who will try to make it equal blame. Don't fall for that propaganda.

Please remember to select a best answer button.

You could say both side and you could also say that neither of the sides are to blame. Both the US ans USSR wanted power so they started, I guess, a stupid competition between each other and then tensions started to get high because both had nuclear weapons that could start another war. However none wanted to have another war because first: both nations had seen the horror of the war and decided to never let it happen again and second: war takes money...LOTS of money and the country was already in debt from the war so they couldn't go to war even if they wanted to. You could blame the greed for power but I think this type of answer is best left to your own opinion on how you see how both countries reacted. Hope this helped :)

Russia