It is often agreed that militarism, the aggressive policy of arming nations, was a chief cause of the wars of the twentieth century between forces loyal to Germany and those loyal to Britain. In a very comprehensive study across 150 years, Colonel T. N. Dupuy uses his experience in the US Army to explain the manoeuvrings and characters behind German warfare in the nineteenth and twentieth centuries. It is the General Staff who influence the performance of the Army, institutionalising military excellence in direct and indirect ways. Colonel Dupuy begins with the Prussian generals of the 1800s including Frederick the Great, and then tells of the alliance between Prussia and Germany in the aftermath of the German victory in the Franco-Prussian War. Colonel Dupuy goes on to write excellently about the two generals named Moltke, uncle and nephew, who steered the German army from the nineteenth to the twentieth centuries. He extols the military virtues of the man whose idea it was to invade France by using the neutrality of Belgium, von Schlieffen, whose plan seemed so brilliant before Britain saw through it during World War I. Following the Treaty of Versailles, which led to the resignations of Groener and the ascendancy of Hindenburg to President, Germany was saved from dissolution and civil war by the brilliant Seeckt. The rise of the National Socialist party, headed by the charismatic Adolf Hitler, made rearmament a pillar of their policies.