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.