THE LATEST “she said, he said” dispute between Democratic presidential candidates Hillary Clinton and Sen. Bernie Sanders (I-Vt.) concerns the federal auto industry bailout. Ms. Clinton charges that, whereas she “voted to save the auto industry,” Mr. Sanders “voted against the money that ended up saving the auto industry.” Mr. Sanders replies that he absolutely did favor an auto bailout and voted for one, but what he opposed was a package of money that would also have rescued Wall Street.

The first point to make about this clash is that it represents, for Ms. Clinton, the wages of her past political responsibility. In September 2008, Ms. Clinton and Mr. Sanders were both U.S. senators deciding whether to vote for a $700 billion fund to prop up the rapidly collapsing U.S. financial system. Ms. Clinton voted yes, on the sound view that the likely alternative to this admittedly undeserved rescue of Wall Street would have been global calamity. Mr. Sanders voted no, demanding that Wall Street pay for its own bailout. As it happens, the bailout fund, known as the Troubled Asset Relief Program (TARP), ended up costing far less than the initial headline figure suggested, and even made taxpayers some money; but, as was foreseeable at the time, that hasn’t stopped the country’s political purists, left and right, from second-guessing and making political hay.

In that sense, Mr. Sanders’s attacks on Ms. Clinton’s vote for TARP were exactly what Ms. Clinton knowingly risked when she nevertheless did the right thing, amid great uncertainty and under tremendous pressure.

Ms. Clinton is indeed being cute by accusing Mr. Sanders of opposing the “money” for the car companies. The record is clear that the senator from Vermont supported an auto bailout in principle and indeed voted for rescuing the industry through stand-alone legislation in late December 2008 (as did Ms. Clinton); that bill failed because of Republican opposition. In the last week of the George W. Bush administration, in January 2009, Congress voted to release the second half of the $700 billion bailout (it had been split into two “tranches”), with the understanding that the incoming Obama administration would use about $4 billion of it to keep Detroit going until a more comprehensive fix could be arranged. It was that measure that Mr. Sanders voted against, because he still couldn’t countenance aid for the banks.

In short, Mr. Sanders favored an auto bailout — on his pure, unadulterated terms. In the real world — the world of compromise, uncertainty and unavoidable haste (the auto industry was nearing collapse in January 2009) — the available bailout was one that came appended to money for the financial sector. And Mr. Sanders voted no. In that sense, the Clinton campaign is quite right to say that, if everyone had voted as Mr. Sanders did, there would have been no auto rescue, at least not the one we got.

Indeed, the episode tends to illustrate rather well the essential differences between Mr. Sanders’s approach to public policy and Ms. Clinton’s. The former preserved Mr. Sanders’s ability to lob holier-than-thou attacks on the campaign trail. The latter helped save the country.