On the macroeconomics of Trump’s budget

That is the topic of my latest Bloomberg column, here is one excerpt:

What’s also striking is that, if the Trump budget can work at all, the spending cuts are probably not needed. It would suffice to cut taxes only, and allow the economy to grow out of an even-greater budget deficit. In this regard, the Trump budget reflects a deep incoherence, and it inconsistently mixes various optimistic and pessimistic scenarios. If the spending cuts are required for fiscal stability, then we probably shouldn’t be doing the tax cuts.

This framework allows us to pinpoint the huge and, I would say, excessively dangerous gamble in Trump’s budget. There is no guarantee that the growth rate of the economy remains higher than the government’s borrowing rate. It is common in American history that government borrowing rates run 5 percent or higher, and the aging of the American population, or perhaps an unexpected catastrophe, such as a war, could lower the growth rate. 1 And once a government becomes addicted to borrowing, it is hard to shake the habit, as subsequent tax increases damage economies.

Do read the whole thing, which focuses on g vs. r…