Tim Weaver asked me about modern monetary theory, MMT, and the resulting conversation made me want to sketch out a small but important argument: MMT is not a left political project.
It is important to make this distinction because of the attention that MMT has received as a rejoinder to claims that the Green New Deal is too expensive: "MMT says that sovereign governments do not face financial constraints, only resource constraints, so we can spend as much as we want on the Green New Deal as long as there is idle capacity." If this constitutes a response to the challenge of affordability, as the story goes, then it has the appearance of bolstering the argument in favor of the Green New Deal by showing that it can be paid for. However, this is mistaken, and MMT is not a good response to the challenge based on affordability. One way to see why it is not good is to see that MMT is not inherently a project of the political left.
The problem is that, in the argument based on MMT, there is no connection between the Green New Deal and the tenets of MMT. The theory, of course, predated the Green New Deal legislation and was brought in as a supporting argument. But the same logic could be used to pay for anything. It is not specific to the Green New Deal: it could be applied to the cost of a border wall. MMT is a politically amphibious idea attached to the left idea of Green New Deal. So when responding to the question of how we pay for the Green New Deal, if we say "MMT," the opponent of the Green New Deal can say, "Ah, we face only resource constraints, so let's use MMT to build gated communities and hire private mercenaries to escape the effects of climate change." If that line of argument is left open, it will be taken, by a desperate right wing.
It seems almost too obvious to spell out, but I will do it anyway: when the right employs MMT, they don't call it anything. They just spend. If we have to respond to an argument about affordability, we have already conceded the essential point.