"…first a Keynesian observes that fiscal stimulus can increase growth in a depressed economy. Second, as an attempted reductio, a conservative says “if that was true, then you could increase growth by breaking a bunch of windows.” Third, the Keynesian accurately points out that you could, in fact, increase growth by breaking windows. Fourth, the conservative accuses Keynesians of wanting to break windows or believing that window-breaking increases wealth. But nobody ever said that! The point is that we have very good reasons to think smashing windows would be a bad idea—there’s more to life than full employment—and that’s why Keynesians generally want to boost employment by having people do something useful like renovate schools or repair bridges."
— Matt Yglesias, leaving out the next line in the exchange; the one where the conservative screams “that’s socialism,” makes a lot of unfounded claims about runaway spending, and then says government initiated stimulus has never worked, and most especially never worked in the guise of the colossal stimulatory effect of government spending to fight WWII. That recovery was the either “power of the markets” or “the markets anticipating Reagan and ‘morning in America.’” As usual.