This means that apart from the difference in ideology that both countries faced, the lack of flexibility from both sides was what made it so difficult to avoid a conflict. Historian André Fontaine, moreover, sees the starting point of the war in 1917 with the Bolshevik Revolution, and suggests that it was mainly due to the aggressive policies of the USSR in foreign policy, dictated by its Communist ideology. The Soviets justify their expansionism in accordance with their Marxist theory which advocated the need to spread revolution throughout the world. On the other hand, some other revisionist historians point at the US foreign policy as the culprit of the origins of the Cold War, culminating in the McCarthy witch-hunts of the 1950s. .
It can also be argued, however, that 'expansionism' and self interest were the reasons why the Cold War started. French historian Alexis de Tocqueville supports this idea and, sort of prophetically, he wrote in 1835 a warning of a balance of power confrontation between the USSR and the USA. This was written before Karl Marx's Das Capital or the 'Communist Manifesto' and long before the Bolshevik Revolution, which leads us to think that the conflict between these countries is not really about ideology. Historians Walter LaFeber and Louis Halle consider the conflict in similar terms, as both see the USA and the Soviets as expansionist powers and therefore, the hostility of the Cold War years was a continuation of the policies they had persuaded since the 19th century. LaFeber writes: The two powers did not initially came into conflict because one was Communist and the other was Capitalist. They first confronted one another in the nineteenth century. []Americans had expanded westward over half the globe and Russians had moved eastward across Asia. Also, Henry Kissinger's writings in the 1980s claim that the USSR's motives were not based on ideology, but rather on self-interest.