[hoopladler]

I'm not the biggest fan of Keynes, myself. I'm assuming that's what you're referencing - since of course, the rest of the industrialized world also enjoyed unprecedented prosperity.

But for my sakes, I honestly think the idea that blowing stuff up just so you can build them again is a bit more abstract than the question demands. After the war, many nations, the USA included, produced large and comprehensive social programs. This undoubtedly wasn't that great for the economy in general (the US share of global GDP steadilly ticked down for the entire period, putting an end to a century of rapid growth). It was however, undoubtedly great for Americans in general.

Between 1975 and today, until a few years ago, American share of world GDP hasn't gone down all that much, indeed, it's descended less than it did in the period between 1945 and 1975. The USA is richer as a nation than it has been at any point in its history. It's simply unwilling to pay for all the New Deal stuff.