If increasing income equality is the goal, it might be wiser to put money into infrastructure than to subsidize manufacturing. Construction also pays good wages, but with lower educational requirements. And America's infrastructure needs are enormous.

The stock market crash in October 1929 didn't destroy a particularly large amount of wealth or make people highly pessimistic. Rather, it made companies and consumers very unsure about future income, and so led them to stop spending as they waited for more information.