Paul Krugman: Learning From Obama

Like many political junkies, I’ve been spending far too much time looking at polls and trying to understand their implications. Can Donald Trump really win his party’s nomination? (Yes.) Can Bernie Sanders? (No.) But the primaries aren’t the only things being polled; we’re still getting updates on President Obama’s overall approval. And something striking has happened on that front.

At the end of 2015 Mr. Obama was still underwater, with significantly more Americans disapproving than approving. Since then, however, his approval has risen sharply while disapproval has plunged. He’s still only in modestly positive territory, but the net movement in polling averages has been about 11 percentage points, which is a lot.