The US Economy Is Great. Stop Worrying About It.

Is it possible for economic news to be a little too good? If many economic worries seem to be dwindling, is that reason to be scared? After periods of success, are economies due for a comeuppance — perhaps even for reasons stemming from their earlier achievements?

What prompts these questions is the current US economy. The good news is evident: Its 2.4% growth rate last quarter exceeded expectations, inflation has fallen to the 3% range, wage gains are finally exceeding price hikes, stock prices have rebounded, measures of volatility have...