Brad DeLong catches someone wondering if I am actually advocating war as a solution to our problems. Against stupidity, the gods themselves …

To be fair, though, I understand from the Times that whenever I mention in my column that WWII ended the Great Depression, the paper gets a lot of mail accusing me of being a warmonger. Amazing.

But maybe this is an opportunity to reiterate a point I try to make now and then: economics is not a morality play. It’s not a happy story in which virtue is rewarded and vice punished. The market economy is a system for organizing activity — a pretty good system most of the time, though not always — with no special moral significance. The rich don’t necessarily deserve their wealth, and the poor certainly don’t deserve their poverty; nonetheless, we accept a system with considerable inequality because systems without any inequality don’t work. And before the trolls jump in to say aha, Krugman concedes the truth of supply-side economics, that’s not an argument against progressive taxation and the welfare state; it’s just an argument that says that there are limits. Cuba doesn’t work; Sweden works pretty well.

And when we’re experiencing depression economics, by which I mean a situation in which it’s hard to create sufficient demand to achieve full employment — mainly because short-term interest rates are up against the zero lower bound — the essentially amoral nature of economics becomes even more acute. As I’ve said repeatedly, this is a situation in which virtue becomes vice and prudence is folly; what we need above all is for someone to spend more, even if the spending isn’t particularly wise.

The trouble in practice is that conventional modes of thought tend to prevail even when they shouldn’t; in particular, public spending on the scale needed never seems to happen. That’s why Keynes facetiously proposed burying bottles full of cash in coal mines, so people could dig them up again: since any proposal to spend money on things we need got shot down on grounds of prudence and efficiency, he proposed completely pointless spending instead.

And what actually ended up doing the trick was spending that was beyond pointless, it was actually destructive – a sort of cruel joke on the part of the gods of economics.

The point is that it would have been much better if the Depression had been ended with massive spending on useful things, on roads and railroads and schools and parks. But the political consensus for spending on a sufficient scale never materialized; we needed Hitler and Hirohito instead.