Hitler came to power at the end of the biggest economic crisis in history at that time. Hitler adopted the national Keynesianism, developed the military industry with the national active fiscal policy, promoted the issuance of bonds and currency, and made the national economy develop rapidly. In the four years since Hitler came to power, the unemployment rate in Germany has dropped from over 30% to almost zero, and the GDP growth has exceeded 100%. At the same time, the construction of German national highway network has been completed, the basic system of heavy industry has been reorganized and equipped with a modern army. But what I want to say is that such Keynesianism is bloody, because the country's active fiscal policy must be driven by enough consumption, but if it can't be consumed, it will only be consumed by war. Hitler's national financial policy is not only to develop military industry, but also to invest in other fields, such as social security reform, such as vigorously funding scientific research. The earliest highway construction in the world was in Germany after the First World War. The purpose of the construction was to enable Germany to transfer its troops from the west line to the east line in one day when fighting on two fronts. But in normal times, this expressway network is also the infrastructure needed by the national economic development. In the 1930s, when the automobile industry was just emerging, it was also the fundamental guarantee to promote the development and consumption of the automobile industry.