To deal with this preference, Keynes whimsically suggested burying bottles full of cash in disused mines and letting the private sector dig them back up. In the same vein, I recently suggested that a fake threat of alien invasion, requiring vast anti-alien spending, might be just the thing to get the economy moving again.

But there are also darker motives behind weaponized Keynesianism.

For one thing, to admit that public spending on useful projects can create jobs is to admit that such spending can in fact do good, that sometimes government is the solution, not the problem. Fear that voters might reach the same conclusion is, I’d argue, the main reason the right has always seen Keynesian economics as a leftist doctrine, when it’s actually nothing of the sort. However, spending on useless or, even better, destructive projects doesn’t present conservatives with the same problem.

Beyond that, there’s a point made long ago by the Polish economist Michael Kalecki: to admit that the government can create jobs is to reduce the perceived importance of business confidence.

Appeals to confidence have always been a key debating point for opponents of taxes and regulation; Wall Street’s whining about President Obama is part of a long tradition in which wealthy businessmen and their flacks argue that any hint of populism on the part of politicians will upset people like them, and that this is bad for the economy. Once you concede that the government can act directly to create jobs, however, that whining loses much of its persuasive power — so Keynesian economics must be rejected, except in those cases where it’s being used to defend lucrative contracts.

So I welcome the sudden upsurge in weaponized Keynesianism, which is revealing the reality behind our political debates. At a fundamental level, the opponents of any serious job-creation program know perfectly well that such a program would probably work, for the same reason that defense cuts would raise unemployment. But they don’t want voters to know what they know, because that would hurt their larger agenda — keeping regulation and taxes on the wealthy at bay.