workers could force employers to grant higher wages by leaving for another firm, which would grant their desired wage increases. It was a form of political resistance that forced Adolf Hitler to go to war in 1939. Thus, the outbreak of the Second World War was caused by structural economic problems, a "flight into war" that had been imposed by a domestic crisis. The key aspects of the crisis were, according to Mason, a shaky economic recovery being threatened by a rearmament program, which was overwhelming the economy; the Nazi regime's nationalist bluster limited its options. In that way, Mason articulated a Primat der Innenpolitik ("primacy of domestic politics") view of the war's origins through the concept of social imperialism. Mason's thesis was in marked contrast to the Primat der Außenpolitik ("primacy of foreign politics") by which historians usually explained the war. Mason believed German foreign policy was driven by domestic political considerations and that the start of the war in 1939 was best understood as a "barbaric variant of social imperialism". Mason argued, "Nazi Germany was always bent at some time upon a major war of expansion". However, Mason argued that the timing of such a war was determined by domestic political pressures, especially those relating to a failing economy, and it had nothing to do with what Hitler wanted. Mason believed that between 1936 and 1941, the state of the German economy, not Hitler's 'will' or 'intentions', was the most important cause of German foreign policy. Mason argued that the Nazi leaders were deeply haunted by the 1918 German Revolution and so were greatly opposed to any drop in the living standards of the working-class since they feared provoking a repetition of that revolution. Mason considered that by 1939, the "overheating" of the German economy, which had been caused by rearmament; the failure of various rearmament plans because of the shortages of skilled workers; industrial unrest caused by the breakdown of German social policies and the sharp drop in living standards of the German working class forced Hitler into going to war at a time and place that were not of his choosing. Mason contended that when faced with the deep socioeconomic crisis, the Nazi leadership had decided to embark upon a ruthless 'smash and grab' foreign policy of seizing territory in Eastern Europe that could be pitilessly plundered to support living standards in Germany. Mason described German