And, crucially, the housing bubble was an international phenomenon: Spain had a bigger bubble than we did, followed by a worse slump. Did U.S. liberals force Spanish banks to make bad loans?

But zombie ideas can’t be killed by evidence. Perpetrators of the liberals-did-it lie are still out there, still getting space to spread their disinformation in mainstream media.

Elizabeth Warren argues that Bloomberg’s embrace of a false right-wing narrative about the financial crisis should disqualify him for the Democratic nomination. But I’d be willing to cut him some slack if he’d admit that he was taken in by right-wing disinformation. If he isn’t willing to make that admission, she’s right.

At the same time that Bloomberg is being called out on his housing bubble zombie, Pete Buttigieg is facing justified criticism for buying into another zombie idea — the obsession with government debt. That obsession did much to hobble recovery from the financial crisis.

To be fair, deficit panic wasn’t as naked a scam as the claim that do-gooders caused the financial crisis, although some of the loudest voices decrying the evils of deficits were obvious phonies. What happened instead was that many important people imagined that inveighing against the dangers of debt made them sound serious, because that’s what all the other serious people were doing.

At this point, however, the debt obsession has been thoroughly debunked by both economic research and experience. We live in a world awash in private savings looking for someplace to go, with investors willing to lend money to governments at incredibly low interest rates. It’s actually irresponsible not to put this money to work investing in the future, both by building physical infrastructure and through programs that help children develop their potential.

Now, the Trump administration is doing it wrong — borrowing large sums, but squandering the money on tax cuts for corporations and the wealthy. But even bad deficit spending boosts the economy to some extent, and it is the reason America is still growing reasonably fast while Europe, still in the grip of austerity ideology, is stagnating.