After losses in all three primaries that took place Tuesday, Sen. Bernie Sanders (I-Vt.) “is going to be having conversations with supporters to assess his campaign,” according to his campaign manager. “Assessing” usually means that the candidate is trying to determine when and how to drop out of the race.

So let us give Bernie Sanders his due.

Sanders was not my favorite candidate among the two dozen contenders for the Democratic nomination, or even in my top three or four. But he has done extraordinary things. He helped reshape the Democratic Party, widened the policy debate in America and inspired millions of followers to a feverish devotion — despite lacking in the kind of charisma we normally associate with successful politicians. It is hardly what you could have expected from a rumpled, grumpy 70-something Jewish socialist.

I’ve been critical of Sanders, even as I was sympathetic to most of his ideas. His theory of governing is grossly inadequate: He had a long slate of plans that would require sweeping legislation, but an almost absurd answer on how any of it would pass Congress. He said his grass-roots movement would be so powerful that it would force even Republicans — even Mitch McConnell! — to vote for programs like Medicare-for-all and free college, measures they find utterly abhorrent.

I suspect that Sanders always understood how ridiculous that idea was but nevertheless decided that repeating it was necessary to avoid compromising his position before he ever took office, and to keep popular mobilization at the center of his political project.

He might not have gotten the chance to test his movement’s ability to make laws. But he proved that you could run a presidential campaign without high-dollar fundraisers, raising over $130 million with contributions from nearly a million and a half Americans. None of his opponents (setting aside the self-financed billionaires) came close on either measure.

And he can take as much credit as anyone — probably more — for the Democratic Party’s movement to the left. Positions that he championed, such as a $15-an-hour minimum wage, went from outside the mainstream to near consensus within the party, in large part because of his advocacy.

Yes, some of the left’s most morally obtuse people rallied behind Sanders, people who draw sustenance from misogynistic Twitter pile-ons and genuinely believe that reelecting President Trump is preferable to seeing a centrist Democrat like Joe Biden occupy the White House for a while.

But they were always a small minority of Sanders’s supporters. He attracted and inspired young idealists, and people willing to invest their time in political organizing, and people who felt that politics and policy could be profoundly different if we simply decided they could be.

That may have been Sanders’s greatest contribution: His insistence that the moral and political compromises we have made and continue to make were not inevitable and ought be questioned. At the very least, they should be examined and understood, and he forced those who assented to them to justify the decisions they had made.

If there’s anything that marks Sanders’s career, it’s the unwavering consistency of his beliefs (with a concession to pragmatism here or there, as on gun rights). You can argue that too much consistency is a problem, and while I’m an advocate of well-considered flip-flopping, Sanders’s unwavering commitment to a set of principles and policy ideas made him a particularly effective advocate for those ideas.

Sanders’s arguments are radical in the sense of getting down to the root of things, always drawing us back to fundamental questions. You may be skeptical about the financing for his health-care plan, but no advocate of a public option, let alone our nightmarish status quo, had a good answer for his oft-repeated question of why the United States is the only highly industrialized democracy that doesn’t guarantee health coverage to every person as a human right.

Sanders has been asking that question (along with many others) for decades, but it was only his two strong presidential campaigns that gave him the platform to force his ideas in front of the entire public, to all of our benefit. He didn’t invent single payer or free public college, but never before in American history have they been the topic of so much serious consideration.

When his 2016 campaign ended, Sanders kept right on going; I’m sure he never entertained any doubt that he’d run again in 2020. But there won’t be a 2024 campaign even if Biden were to lose in the fall (Sanders will be 83 by the next election, too old even for him). Knowing that, he’s surely reluctant to turn out the lights on this campaign.

Although I recently argued that Sanders should stay in the race as long as he wants, there are good reasons for him to bow out now, not least of which is the risk of people gathering at polling places and transmitting the novel coronavirus if the primaries go on. But I’m guessing he knows that once he’s no longer a presidential candidate, his ability to command attention and wield influence will decline precipitously.

After this, he won’t be just one of a hundred senators — he’ll still be able to get on the Sunday shows and get attention for himself — but maintaining a movement after a campaign shuts down is an extraordinarily difficult task, let alone successfully mobilizing that movement to shape the course of events.

Which means that Sanders has reached the apex of his career and his cause. It might not have gotten him to the White House, but it did more than just about anyone thought it would.

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