How did World War 2 benefit the US economy? Was it a case of massive Keynesian fiscal stimulus?
Although there was massive export growth thanks to the Lend-LeaseW program, starting prior to the USA's entry to the war, payment was deferred, so there was no input to the economy from this. Also, overall exports to Europe would have dropped enormously[verification needed] so the external economic environment was worse.
This is a crucial question for the present-day world, looking at the need to tackle climate change, with calls by some for action comparable to wartime measures. Some are fearful of the economic impact - how valid are these fears?