Who was to blame for the outbreak of the Cold War?

The origins of the Cold War have been a major source of historiographical debate amongst scholars. Broadly, there are four schools of thought that are important to know of. The first is the Pro-Soviet account notably argued by E.H Carr, which believed that Soviet Communism was the major progressive force in the world, the US was the main obstacle to its progress and consequently, blamed the Cold War on American aggression and expansionism first in Europe then across the globe. It is worth stating that this school of thought is largely dismissed among historians today. The second, more important, approach is the orthodox one embodied by historians such as Thomas A. Bailey, George F. Kennan and Hebert Feis. These historians argued that the Cold War erupted as a result of Soviet aggression and expansionism in Eastern Europe which, in Kennan's words, needed to be "contained". For example, Bailey argues that it was Stalin's violation of agreements made at the Yalta and Potsdam conference that caused the breakdown of relations between the Allies. This approach suffered criticism in the 1960s notably during the Vietnam War when American imperialism became increasingly apparent in the eyes of the world. William A. Williams is largely seen as the first revisionist historian arguing that America had always been an empire-building nation and that the Cold War was mostly a consequence of this imperialism. Revisionism rejected the premise of "containment" arguing that what was seen as Soviet aggression in Eastern Europe was in fact inspired by a defensive rationale and that America's hegemonic aspiration was more to blame than anyone or anything else for the outbreak of the Cold War.The last and more interesting school of thought is post-revisionism. Notable post-revisionist historians include J.L. Gaddis, M. Leffler and V. Mastny. It is very difficult to generalise what the position of this school of thought is since post-revisionist historians debate amongst each other, but most have adopted a more nuanced view regarding the origins of the Cold War. Gaddis argues that both Soviet aggression and American expansionism played a role in bringing the conflict about, but he also emphasises the importance of Stalin arguing that it is only when one removes him from the equation that it becomes possible to envisage the Cold War not taking place. Leffler argues that what really mattered was the (mis)perception that each superpower had of the other, and Mastny believes that it what the Soviet system that Stalin had created which made the Cold War inevitable. Overall, it is difficult to say who was responsible for the Cold War as it was a multi-dimensional conflict which had multiple causes, but it is among the post-revisionists that one should look for convincing answers to this question.