You know, the Keynesians have an answer for that. Roosevelt actually cut government spending and increased taxes before the 1937-38 recession, which is certainly one way to explain the deflation and the unemployment (which is why many Keynesians consider Roosevelt to be only mildly Keynesian). Milton Frienman disagreed, of course; by him, it was restriction of the money supply which caused the deflation. Either way, it’s certainly no argument for Austrian style economics, which favors restricting the money supply with high interest rates.
And while unemplyment was bad (a common result of deflation), the GDP continued to grow from 1933 to 1937, when it declined slightly, but was already increasing again before the war began.
Major wars of course do help the economy, and Keynes even mentioned war as a possible event that could offset a depression (of course he wasn’t suggesting war as a solution, merely acknowledging the fact). After all, war does boost aggregate demand tremendously, the products demanded being tanks, bombers, and aircraft carriers.
All the Ohioans flooding into the sunbelt would then be illegals. The Arizonian would have to fend us Midwesterners off from all sides. And the Southerners, I’m sure, would throw a fit at the prospect of having to teach English in their schools to accomodate the Northern border-hoppers fleeing the invading Canadian cold fronts.