Drugs

"German troops did not conquer Poland and Czechoslovakia thanks to a pill called Pervitin;" nevertheless it may have played a role. About Blitzed, from the LA Review of Books.

It was almost as easy to obtain after the war.

I wonder what social effects were associated with widespread use of meth. Alcohol, khat, marijuana, meth... Thought experiment: these have different psychological effects when you abuse them; if even only 10% of the population abuses one, that should have some cultural effects--even if only in stereotypes and expectations, but surely in things like the associations you have with ideal recreations. That would be very hard to tease out of other effects. Availability depends on where you are, and your neighboring cultures influence your culture too. And your culture will effect what drugs are more popular. You probably can't find causation.