Donald Trump was totally incoherent about the economy.

Trump’s presidential run is essentially based on two things: His assertion that he, and only he, can bring border security, and his argument that his ability to successfully run a business makes him qualified to be president. But in the section of the debate devoted to the economy, Trump’s answers were disingenuous at best and stupid at worst.

Most egregiously, Trump compared the United States’s economy to that of India and China—telling the audience that because the United States is not growing as fast as these emerging economies, it should be treated as a failure. “I just left some high representatives of India, they’re growing at 8 percent. ... We are growing at the 1 percent level and I think it’s going down.”

This is an absurd argument: The reason developing economies grow at such a fast rate is that they are in the midst of industrialization. If the U.S. economy, a fully industrialized economy, grew at an 8 percent rate, the Federal Reserve would have to step in to prevent it from overheating.

I had always assumed that Trump shied away from talking about the economy because it is doing OK. But maybe it’s because he knows nothing about basic economics.