Explanation: Early on in WW2, the Nazi regime relied heavily on meth as a drug to keep its soldiers going during combat operations - most notably during the Fall of France, during which Nazi tankers hopped up on meth would fight for several days straight without sleep, putting the French defenders at a massive disadvantage.
The Allied powers would use amphetamines (especially for pilots as 'go pills') but not on the scale of the Nazis (with the Nazis producing and distributing more meth each year, than all of the Allies combined produced amphetamines for the entire war), and largely not fucking meth.