<P> Although explanations of the origins of the conflict in academic discussions are complex and diverse, several general schools of thought on the subject can be identified . Historians commonly speak of three differing approaches to the study of the Cold War: "orthodox" accounts, "revisionism", and "post-revisionism". </P> <P> "Orthodox" accounts place responsibility for the Cold War on the Soviet Union and its expansion further into Europe . "Revisionist" writers place more responsibility for the breakdown of post-war peace on the United States, citing a range of US efforts to isolate and confront the Soviet Union well before the end of World War II . "Post-revisionists" see the events of the Cold War as more nuanced, and attempt to be more balanced in determining what occurred during the Cold War . Much of the historiography on the Cold War weaves together two or even all three of these broad categories . </P>

Which of the following was one of the major causes of the cold war