The doctrine for winning wars lists a few basic points: motivated men (training), logistics at a scientific level (production and transport), knowledge of the terrain and the enemy (intelligence - humint, sigint and imint), firepower (tactics) and air dominance, which has always been well placed in military strategy since the Second World War.
To fund and support the above requires a country with large amounts of capital, a strong economy and manufacturing capacity.

If the reader takes the time to read the articles that paint a bleak overall picture of the economies and armies of Italy, Germany, England and the United States in the pre-war period, it will be clear that, despite the many economic and political contrivances, neither American nor European capital was able to provide a way out of the economic crisis that plunged the world into the Second World War.
Some time after the end of the conflict, the American Douglas North, Nobel laureate in economics, said: "We did not get out of the Depression because of economic theories, we got out of it because of the Second World War". Between 1935 and 1940 the number of unemployed had not changed significantly (about 10 million people); after 1937 industrial production collapsed by 27%, but with the start of the war things changed and in just six years (1939-1945) unemployment was reduced from 10% to 1%. This shows that the Second World War was a clash of capitals, in which the United States finally asserted itself at the expense of Great Britain, becoming in all respects the locomotive of the capital mode of production.

Consequently, one can imagine the amount of equipment, aircraft, ships, tanks and thousands of other items that were programmed, researched, developed and produced by the industry of the Allied countries, and especially the American industry, in a very short time, to say the least, between 1939 and 1945.

It thus becomes well evident the financial, economic and manufacturing power that the Axis forces were up against.
What is most incomprehensible is that their leaders were well aware of this when they decided to enter the war, and even more so when the conflict expanded to include first their former ally Russia and then the United States.

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