I won’t (and can’t reasonably) dispute that it was WWII that ended the depression.
But neither can it be disputed that government spending was cut sharply in ’37, most as a result of those concerned with mounting government debt. Followed by a > 30% increase in unemployment. Followed by a return to large scale government spending (I think it was close to $5 billion in stimulus). Followed by the end of the recession. Beginning to end was less than 2 years.
That said, employment didn’t return to pre-recession levels until a few years later when the US entered WWII. Would it have happened without the war? Probably not with the speed and endurance that it did.
But I have to add here. Top marginal income tax rates for those making over $20,000 a year (I’m guessing pretty decent money at that time) almost doubled to 55% after US engagement. For the very wealthy, it rose to 89%, and then to over 90% where it stayed for the duration of that war and the next. And the economy exploded (in a good way) with those high tax rates. JM would have approved.
