I haven’t paid much attention to François Hollande, the president of France, since it became clear that he wasn’t going to break with Europe’s destructive, austerity-minded policy orthodoxy. But now he has done something truly scandalous.

I am not, of course, talking about his alleged affair with an actress, which, even if true, is neither surprising (hey, it’s France) nor disturbing. No, what’s shocking is his embrace of discredited right-wing economic doctrines. It’s a reminder that Europe’s ongoing economic woes can’t be attributed solely to the bad ideas of the right. Yes, callous, wrongheaded conservatives have been driving policy, but they have been abetted and enabled by spineless, muddleheaded politicians on the moderate left.

Right now, Europe seems to be emerging from its double-dip recession and growing a bit. But this slight uptick follows years of disastrous performance. How disastrous? Consider: By 1936, seven years into the Great Depression, much of Europe was growing rapidly, with real G.D.P. per capita steadily reaching new highs. By contrast, European real G.D.P. per capita today is still well below its 2007 peak — and rising slowly at best.

Doing worse than you did in the Great Depression is, one might say, a remarkable achievement. How did the Europeans pull it off? Well, in the 1930s most European countries eventually abandoned economic orthodoxy: They went off the gold standard; they stopped trying to balance their budgets; and some of them began large military buildups that had the side effect of providing economic stimulus. The result was a strong recovery from 1933 onward.