Blame Polarization for Tepid Economic Growth?

Chalk up another reason to worry about intensifying political polarization.

There has been a running argument among economists on the extent to which uncertainty over U.S. government policy –taxes, spending and regulation – is a big reason the economy has been so distressingly sluggish.

In a skirmish over the weekend at the annual meeting of the American Economic Association, Harvard’s Larry Summers challenged the case that uncertainty is a big problem: Do I want my doctor to be “consistently predictable or responsive to” a particular health emergency, he asked. Better,...