More interesting than my overall grade are its components. For the first six months, I’d award him an A-; for the rest, a C- or D. I’d weigh the two grades equally, because he deserves a lot of credit for stopping the economic free-fall when he took office…

To be fair, the weak recovery has other, larger causes: the hangover from the financial crisis and Great Recession. The burst real-estate bubble destroyed $6 trillion of housing values. Rebuilding their wealth, many Americans are repaying debt and saving more. This depresses consumer spending — the economy’s main engine — which is growing about 2 percent annually, down from 3 percent before the crisis, notes Behravesh. Likewise, the failure of housing construction to revive has hurt this recovery compared to most others, argue economists Michael Bordo and Joseph Haubrich in a new paper.

But Obama’s missteps have made the situation worse. How much? The honest answer: We don’t know. Economists’ efforts to measure the impact of “policy uncertainty” are primitive. My guess is that Obama’s errors had a modest effect. Suppose they cost 25,000 jobs a month. Beginning in 2010, job growth has averaged about 125,000 a month. The extra 25,000 conceivably might have strengthened confidence and accelerated the recovery.