Bernie Sanders supporters’ reaction to Elizabeth Warren’s speech at the Democratic National Convention last night served as a measure of how specific and fast political change can be. PHOTOGRAPH BY PHILIP MONTGOMERY FOR THE NEW YORKER

“People get it,” Elizabeth Warren said at the Democratic National Convention last night. “The system is rigged.” That line was heard often yesterday, in the Wells Fargo Center and in the streets of Philadelphia, but in all the repetition it lost some of its specificity and power. What system, exactly, and rigged for whom? Warren’s version was narrow: the laws shaping the economy had been perverted so that the country was congenial for the rich and brutal for the poor. But the Bernie Sanders supporters, who by shouting kept control of the hall for much of the evening, had in mind a broader corruption, one that took in the Democratic Party, too. This left Warren in an ambiguous position: she was both an ally of the revolution and implicated by it. “My good friend,” Sanders would call Warren, with feeling, when he spoke later in the night—a reminder that, until his campaign for President, Warren had been regarded as the major progressive force in the Party, and that his movement and hers were not so easy to separate. But the Massachusetts senator maintained a studied neutrality in the primaries, declining to endorse until she backed Clinton after the outcome had been decided, and during her speech some Sanders supporters booed her, too. “We trusted you,” some shouted d (as my colleague John Cassidy noted). Reporters took the shouting as a sign of the general unruliness of the Sanders faction, proof that its core members had turned on even their own natural allies. But it was also a measure of how specific and fast political change can be. The revolution that moved through the Sanders campaign no longer seemed to have much to do with Warren.

The protests yesterday had been larger than expected, first in the heat downtown and then in the rain in a park near the arena, and the question that surrounded them was whether Sanders’s supporters would really return to the Democratic Party. If Warren was the progressive whom the Democrats offered to heal the rift, then the other possibility was represented by the Green Party’s candidate for President, a retired physician named Jill Stein, who, like Warren, is a woman in her mid-sixties, lives in the well-ordered and prosperous suburbs north of Boston, and has been on the faculty of Harvard. Stein is a movement figure with movement aesthetics: she sleeps on the couches of supporters and makes personal calls for small donations; she represented, as Sanders did, a certain political innocence. “To have those kinds of policies, you need that purity,” Daniel Sloane, who had been for Sanders and was now for Stein, told me early yesterday evening, while he was hanging a Green Party banner in F.D.R. Park. Handmade signs repeated Stein’s denunciation of the idea of Clinton as the “lesser evil.” There was a general truculence about the notion that the threat of Donald Trump should compel progressives to shuffle into line behind the candidate. “To have everything nullified just because the Republicans nominated a bogeyman doesn’t sit well with me,” Kevin Castaneda, a young Sanders supporter from Philadelphia who was weighing Stein and Clinton, said. “We shouldn’t allow ourselves to be engulfed by fear.”

Within the Massachusetts delegation, as it awaited the evening’s speeches, it was possible to hear these tensions in the ways that the delegates talked about Warren. To the Party’s leaders, she was proof of how progressive Democrats had become. “She’s a strong voice for those things that we as Democrats really believe in,” Thomas McGee, the chair of the Massachusetts Democratic Party, said, noting the progressive turn that the national Party had taken on income inequality, L.G.B.T.Q. rights, and green jobs. To the Sanders supporters, Warren showed the limits of how far the Party could go, and how it would talk. “She strikes me as more the intellectual, limousine liberal, who talks the right talk but doesn’t have the sensitivity to know what it feels like to be unemployed,” Steven Camara, a city councilman from Fall River, a small working-class city, told me. He said there was a lot of enthusiasm for Trump in Fall River, in ways that reminded him of a “massive” crowd he’d watched George Wallace draw nearby in 1968, and it made him think a more direct approach was warranted. Andrea Burns, a Sanders delegate who had been a city councilwoman in Easthampton, recalled the excitement she felt at an early Warren house party, and the power of Warren’s outrage over inequality, when the Harvard law professor was first exploring a run for the Senate. Burns was disappointed that Warren had not endorsed Sanders, but she also preferred the scope of the Vermonter’s politics, his emphasis not just on inequality but on the failures of American foreign policy and campaign-finance regulation. “The broadness of it, the totality of the vision was so compelling,” Burns said. Among the New England Sanders supporters, there was a sense that Warren had only wanted a partial revolution. If the point of the movement was to take the country back from the bankers, why be so eager to hand it over to the lawyers?

Warren has been the object of various forms of progressive pining during this election cycle. First the hope was that she might run for President, and then—especially after she appeared onstage with Clinton, in Cincinnati, a matched pair in blue blouses—that she might be chosen as the Vice-Presidential candidate. The yearning for Warren followed from the conviction that moral authority might derive from intellectual authority, that the Harvard Law School bankruptcy expert was best equipped to explain the hole that the financial crisis had put us in. But it also had a personal intensity: there was something winning about the idea that the first woman President might be someone whose husband had nothing to do with her career, and that a janitor’s daughter from Oklahoma could achieve first fame and then political power by rigorously describing the forces that had afflicted her. Early this summer, she’d picked up on the fact that Trump had said, just before the start of the financial crisis, that he was “excited” for a collapse because it would let him scoop up properties on the cheap. She contrasted Trump rooting for a catastrophe with the families who had suffered from it, the children who had slept in cars. Last night, talking about the six times that Trump had filed for bankruptcy, she emphasized not the Republican’s incompetence but his moral cowardice, the way that bankruptcy had allowed him to “protect his own money and stick his investors and contractors with the bill.” She wondered, “What kind of man does that?”

The continuing battles within the Democratic Party are in part about how the story of the financial crisis is told, and the degree to which it should reorder politics. The stakes aren’t only those that Sanders describes. If Americans feel ambivalent about the government and its regulation of the economy, then that is a problem for Democrats in the Presidential election, because a Democrat has been the President for nearly a decade and cultural power belongs to liberals. The story that Warren told gave the Party an answer, because she did not see a collapse of institutional authority or politics but, rather, a persistent set of corruptions in which the systems of regulation bent toward a very few, very wealthy people. Follow this line, rather than Sanders’s, and it leads back into the Democratic Party, where campaigns against concentrations of wealth have a natural home. Inequality, in Warren’s hands, gave the Party’s program of inclusion a specific weight. “When we turn on each other, bankers can run our economy for Wall Street,” she said last night. The line on Warren, during the past month, is that she has become Clinton’s designated attacker. The more interesting truth may be that she has become, more completely, a Democrat.

Warren was subdued last night, conversational in an angry room. The Washington Post named her among the night’s “losers.” The necessity of her appearance was clear—she was the Party’s way of demonstrating allegiance with the insurrection—but Warren’s seduction was at once too obvious and too limited: she mentioned a “rigged system” five times, but only on her own narrow, economic terms, not theirs. Sanders, who followed her, said he was proud to report that his camp and Clinton’s had come together to produce “by far the most progressive platform in the Democratic Party,” with calls for a federal minimum wage of fifteen dollars per hour and for breaking up the largest banks. That this is now the center of the Party owes a great deal to the political energy of the Sanders movement. It owes at least as much to Warren, who gave Democrats a way of talking about the financial crisis that was precise, avoided the usual abstraction, and named a culprit. This week, when her language and the language of the Party’s establishment came to echo each other, it sounded to the Sanders core like capitulation. From other angles, it sounded like conquest.