Why did the industrial output of the United States during the war astound the rest of
the world?

The automobile industry was uniquely suited to the mass production on military equipment. They began to produce trucks, jeeps & tanks. They also produced artillery, rifles, mines, helmets…etc. Henry Ford launched one of the most ambitious projects when he offered to create an assembly line for the enormous B-24 bomber.

Explanation:

missouri compromise of 1820 which prohibited slavery

a system of cooperative federalism emerged, as the powers of the federal government expanded.