Carolyn Kaster / John Locher / AP

On June 27, 2019, just under an hour into the first Democratic primary debate, Kamala Harris turned her attention to the front-runner, Joe Biden. A week earlier, during an event in New York City, the former vice president had riffed about his relationships with segregationist senators, such as James Eastland and Herman Talmadge, to illustrate a point about civility and compromise in politics. Harris, who was the only Black person onstage that night, took offense. “You also worked with them to oppose busing. And there was a little girl who was a part of the second class to integrate her public schools, and she was bused to school every day,” Harris said. “And that little girl was me.”

The moment vaulted Harris into the lead in several national polls. And it earned an apology from Biden (“Was I wrong a few weeks ago?” he asked a crowd in Sumter, South Carolina, a few days later. “Yes, I was. I regret it, and I’m sorry.”) This week, the Trump campaign quickly seized upon the dustup. “Not long ago, Kamala Harris called Joe Biden a racist and asked for an apology she never received,” Katrina Pierson, a senior Trump-campaign adviser, said in a statement, despite Harris prefacing her debate-night remark by explicitly noting that she did not believe Biden was racist.

Ultimately, Biden and his staff were able to look past that night. In late July, a photographer captured a shot of Biden’s personal notes at a campaign event in Delaware where, beneath Harris’s name, he had jotted “Do not hold grudges.” But whether the two—now historically joined as Democratic running mates—like it or not, their brief exchange last summer will loom over their ticket long after Election Day.

Whereas Trump supporters see this as a weakness, Biden supporters are spinning it as a strength. “I think that Joe Biden was a bit surprised by the question, but I do believe that Kamala Harris demonstrated that she is willing to take the fight to the opponent,” James Clyburn, the South Carolina Democrat whose endorsement boosted Biden’s candidacy across the South, told reporters on Tuesday. “That question is a furtherance of what makes Biden respect her so much.” Clyburn pointed to Justice Brett Kavanaugh’s Supreme Court confirmation hearings as another example of Harris showing her character. Harris’s camp might also point to the confirmation hearings for Attorneys General Jeff Sessions and William Barr as times when she has not shied away from confrontation but run toward it—a helpful skill as she prepares to debate Vice President Mike Pence this fall.

Biden’s selection of Harris may also signal that he is willing to be challenged himself, Christina Greer, an associate professor of political science at Fordham University, told me. “That he still chose the same woman who critiqued him as his closest partner to rebuild American democracy speaks very highly about how Joe Biden views female leadership and the ability for someone to call him to the mat,” she said. He will “get back up, shake hands, and be willing to listen and learn.”

Progressives hope that, just as Biden signaled he’s willing to be pushed by Harris on race, perhaps he will be willing to be pushed on other issues. They hope Biden will expand his narrow vision of police reform and embrace student-debt cancellation, or, as an easier issue, recant his aversion to legalizing marijuana.

Perhaps more than anything, Harris’s attack on the debate stage illuminated the ways well-meaning people can be complicit in systemic racism. The segregation in public schools across America, for example—seen in the micro-districts of Connecticut and school-district secessions in Louisiana, both of which isolate students of color from financial resources they need—is driven not only by racists, but also by white liberals who would prefer to send their kids to “good schools.” The people who believe that local areas where segregation is entrenched will integrate of their own free will, as was argued when busing was at its height, help prop up an unjust system. On knotty issues like school segregation, Greer told me, “having someone who understands the problems—who has been a part of this system—brings a special level of knowledge.”

Before Tuesday’s announcement, I asked Bakari Sellers, a Democratic former state representative in South Carolina, what impact that moment in the debate would have on Harris’s vice-presidential prospects. He argued that, if anything, it enhanced them. “It was tenacious,” he said. Then he came back to the significance of having a Black woman on the ticket, what it means for this moment of national protest. “She brings the relevant life experience to this moment. It’s hard for people to say that we’re going to fix the problems that are highlighted by [the death of] Breonna Taylor with people who don’t look like us.”

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