Who’d a thunk it?

In the post-mortem of the Democrats’ Tuesday night debate, the consensus among the chattering class was that Pete Buttigieg not only had a strong night but also, in challenging Elizabeth Warren’s “Medicare for All” plan, emerged as a moderate alternative (along with Joe Biden) to socialist Bernie Sanders and the like-minded Warren. And, of course, as the moderate alternative to Biden himself.

The 37-year-old openly gay mayor with a schoolteacher husband at home in South Bend, Ind., is the moderate alternative.

A veteran who served in Afghanistan and a Rhodes scholar from the heart of the Midwest, he is the most knowledgeable about foreign policy, the most reasonable about taxes and the most respectful of Americans’ ability to make economic decisions for themselves.

Fifty-one percent of America is not to Pete Buttigieg’s left.

No one is going to beat Trump running from Mayor Pete’s left.

And why should they try?

The mayor’s best moment of the night was Warren’s worst, meaning it gets replayed twice as much. For something like the 18th time, she refused to admit that paying for Medicare for All is going to result in tax increases for the middle class. Of course it is. This is a Bernie Sanders plan. And Bernie has said, at least as many times as Warren has ducked, that the most expensive new program in government history will require more taxes. Instead, Warren keeps talking about “costs” dropping — meaning you don’t have to pay premiums and copays (although you do under Medicare, unless you have a private supplement, which will presumably also be gone, making the tax expense here astronomical). The hope is that these “costs” will go down more than your taxes will go up, which may be likely if you’re an older person making a fixed income but not so likely if you’re younger and healthier. Why not admit it?

“Read my lips: no new taxes.” So sayeth then-President George H.W. Bush, after trouncing Bob Dole in New Hampshire for refusing to take the New Hampshire pledge to not raise taxes. Four years earlier, at the Democratic National Convention, Democratic nominee Walter Mondale had boldly announced that whoever would be elected president in November would raise taxes. “He won’t tell you. I just did,” he said of Ronald Reagan, the Republican nominee. Reagan hammered him. Mondale lost in a landslide.

The game is called “Gotcha!” Warren is determined to avoid a tape that has her saying, “Yes, of course I will raise your taxes, but (at least for Americans with big medical expenses or low salaries) that increase will be outweighed by the savings on premiums and copays.”

Of course it’s true. But the “Of course I will raise your taxes” clip would open every episode of “The Sean Hannity Show” between now and the election. There would be no end to calculations about how much more in taxes you would be paying for worse coverage than you have now.

But the underlying problem is Warren’s to solve. Bernie is who he is, which is why no one thinks he’ll be president. Warren has surged as a straight-shooting Bernie with a chance. But Warren has to know that she can’t win as the Cambridge Bernie. And it’s Mayor Pete, no right-winger he, who wonders not only how she is going to pay for Bernie’s plan without the taxes he concedes but also why she can’t answer a yes-no question and why she doesn’t trust Americans to know what’s best for themselves.

Susan Estrich is a syndicated columnist.