Mike Segar / Reuters

Democrats who watched the second debate on Thursday probably thought their party had a good night. It did not, and they should worry.

Their first worry is the weakness of former Vice President Joe Biden. He has led the Democratic pack—and he polls well with the larger public—on the strength of his offer of a return to normality after the maelstrom of the Trump presidency. The big doubt about Biden: Can he cope with the ferocious malignancy that is Donald Trump? When Trump roars and raves, abuses and insults, can Biden meet and master the obscenity of it all?

Last night, Biden showed that the answer is probably: no. The evening’s most dramatic moment was Senator Kamala Harris’s attack on Biden’s racial record, prefaced with a condescending, “I don’t think you’re a racist.” The attack was delivered with all the unpredictable spontaneity of a speech by one of the animatronic characters in Disney’s Hall of Presidents. Biden knew it was coming. He had answers ready. And yet, they were inadequate: bureaucratic, incomprehensible, faintly aggrieved. This was the moment for Biden’s “man in the arena” speech. I’ve fought the good fight, lost some, won more—it’s harder than just talking, you know. My name is on a hundred pieces of legislation that have made life better for Americans of every race, every background, men and women.

Tell me about the bills you’ve passed, Senator. He heard the question, but not the question behind the question: If you cannot cope with this cheap, preplanned line of attack from Harris, how will you cope with the manic aggression of Donald Trump?

Biden’s debate staff had drilled him hard ahead of this debate. The lesson they had pounded into him was, apparently: Don’t talk too much. Wait your turn, respect the clock, stick to the point. That lesson seems to have so filled his head as to have left scant room for anything else. The enduring takeaway from the most dramatic exchange of the evening might have been: That was a manipulative performance by somebody deliberately refusing to understand the work a successful politician must do. Instead, it was: Biden tripped over a two-inch-high bump in the pavement. What will happen when he reaches a vast gap in the sidewalk filled with filthy mud?

The second worry is the weakness of the next tier of normal Democratic candidates—especially Harris—in the face of left-wing pressure. In a single evening, Harris endorsed abolishing private health insurance and offering taxpayer-funded health care to unauthorized immigrants, and opposed the deportation of unauthorized immigrants who have not committed criminal offenses. “A mother who pays a coyote to transport her child,” she began one sentence, but instead of warning against human trafficking, she ended by insisting that the mother and child be allowed to stay. Harris committed herself to a left-wing base-rallying strategy in ways she will not easily escape—in a party whose left-wing base is quite a tiny portion of America as a whole.

The third and final weakness of the night was the unwillingness and inability of any of the candidates—except, quietly, Biden—to defend their party’s most important domestic reform since the Lyndon Johnson administration: Obamacare. The Affordable Care Act was passed when Democrats held a 60-seat majority in the Senate. If you believe it’s a shabby, pitiful, unworthy half measure, then other than magic wishing pills, there’s no strategy for you ever to enact anything you will regard as successful. And denouncing it in those terms is an indictment of the last president, the one who, to this day, remains a talismanic name among the voters these candidates most need to mobilize.

Things may change by November 2020, but in the summer of 2019, polls show an American electorate that is more content with its own personal situation than at any time since the second Clinton administration. President Trump has not (yet) been able to capitalize on that satisfaction, because so many voters are repelled by him personally. But there is little appetite in this country for big radical reforms such as stripping people of their existing private-sector health insurance. There will be even less appetite when the next administration tries to finance that reform by raising taxes, as the candidates last night acknowledged they will have to do.

Democrats won on Obamacare. They beat back almost a decade of Republican efforts to repeal it. But they won’t accept success as an answer, and so they won’t allow their party the moral and political rewards of success. They are competing for the support of the angry voters they read on Twitter—overlooking the many millions of people uniquely available to the non-incumbent party in what should be a pro-incumbent cycle.

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