It is difficult to say that the second phase of the Industrial Revolution caused the First World War, but is certainly the case that it helped to create an atmosphere in which such a war could occur. Many of the more direct causes of the war, for example, were shaped by the social and technological changes that took place in the four decades or so before the conflict. One of the major reasons for the conflict was the military buildup at the beginning of the twentieth century, which created tensions between the powers. This buildup was, of course, exacerbated by the development of heavy industry, which was put to use manufacturing new weapons and especially, in the case of Britain and Germany, modern warships. Additionally, the desire to avoid industrial overproduction was a major incentive for imperialism, which also led to increased tensions between the powers. Finally, some have argued since the war (and, indeed argued at the time) that the military elites in Germany and elsewhere were motivated in part by anxieties about the increasingly radicalized working classes in their countries as they made the decisions that led to war in 1914. This position is most associated with Marxist historians such as Arno Mayer, though many socialists, in particular, argued exactly this at the time. It should be reemphasized that these factors were in no sense direct causes of the war, but rather exacerbating factors.