Most elections are defined by moments of confrontation: a debate stage swipe, a hard-hitting attack ad, or a scathing quote from a surrogate in the bowels of a spin room.

Last week, however, the biggest moment in the Democratic presidential primary—one with potentially major ramifications for the general—involved a form of strategic détente. And the question now confronting each side involved is whether it was wise.

On Monday, Bernie Sanders apologized to Joe Biden for an op-ed that one of his supporters wrote in which she accused the ex-VP of having a “big corruption problem” that needed to be addressed. The piece, which had been written by law professor Zephyr Teachout and spread by Sanders’ campaign, had come on the eve of the Senate impeachment trial centered on President Trump’s efforts to dig up dirt on Biden under the shaky guise of rooting out “corruption” in Ukraine.

Days later Sanders once again sidestepped the chance to put the screws to his primary rival, saying he saw no merit to having Biden or his son Hunter testify during the impeachment proceedings in exchange for witness testimony from someone from the Trump administration.

On the surface, Sanders’ decision makes sense. The case against Biden is based largely on drummed up smears orchestrated by Trump allies. It has little to no relevance to the actual impeachment hearing. And, moreover, it doesn’t take a poli-sci degree to see how Sanders benefits from taking the high road while his aides inject talk about an opponent’s weaknesses into the media bloodstream.

But not everyone in progressive circles believe it was savvy or smart for Sanders to distance himself from Teachout’s piece. Matt Stoller, a largely supportive voice for the senator, saw a missed opportunity; not for Sanders’ candidacy per se, but for airing out an issue that needed to be litigated by Democrats.

“It's a moral and political crisis for Democrats that we cannot reckon with the obvious bribery taking place among our top leaders,” said Stoller, referencing the private sector success that Biden family members have enjoyed, largely on the basis of their last name.

For Team Biden, the accusations surrounding the former VP and his family don’t need to be litigated precisely because—in their estimation—they are baseless. While Hunter Biden may have acknowledged that his post on the board of a Ukrainian natural gas company was likely the product of his famous dad, there is no case to be made that he acted corruptly or that he compelled his father to pull strings on his behest. For that reason, Joe Biden has rejected the notion that he should testify as part of the impeachment trial. As have his allies. A proposal that he do so, in exchange for former National Security Adviser John Bolton testifying, was never seriously considered, multiple sources said, even though it was floated by Sen. Chris Coons (D-DE), a close Biden ally.

“ It wasn’t planned out and it’s not a real discussion,” said one Senate Democratic aide.

Biden’s campaign has, nevertheless, tried to address the accusation of corruption by parlaying it into a political advantage. His campaign has framed the issue as an implicit recognition that the president views Biden as his most dangerous opponent. They’ve run online ads around impeachment that adopt the “Trump vs. Biden” frame and have encouraged TV networks not to book the president’s lawyer, Rudy Giuliani, on grounds that he’s peddling baseless smears.

Whether that’s sufficient is a question that non-affiliated Democrats have been grappling with in recent weeks, especially as Republicans—notably Sen. Lindsey Graham (R-S.C.)—have signaled that they intend to launch investigations into Hunter Biden’s role at Burisma following the conclusion of the impeachment trial.

The analogy is imperfect, but during the 2016 primary, Sanders similarly took a pass on joining attacks on his leading rival’s ethics. His famous insistence to Hillary Clinton that the country was “sick and tired” of hearing about her “damn emails” provided both an iconic moment, an affirmation of the idea that the senator was substance-focused, and—not insignificantly—a massive fundraising boon. What it did not do, however, was prevent Clinton from securing the nomination.

After Trump’s win, there was a school of thought that Clinton would have benefited from Sanders having taken off the gloves; that being forced to litigate the email issue during the primary would have honed her defense of it and made the matter seem less novel when it was weaponized against her in the general election.

But as time has passed, theories on this have changed. As one longtime Clinton confidant put it: “She could have started to address it when she was in high school and it wouldn’t have mattered. There was no answer that would have satisfied people.”

Few see parallels between ‘16 and ‘20. Clinton, after all, came into the race with a perception (fair or not) that she had a lax moral compass and played by a different set of rules. Her exclusive use of a personal email address and private server only reinforced that prior. Biden doesn’t suffer from the image of being someone who has traded off of his political perch.

“It's not even apples to oranges,” said one Biden aide, “it is apples to airplanes.”

And yet, there is fear that if Biden doesn’t address the matter more forcefully now, it could take root in damaging ways; that, as one senior Democratic strategist put it, “once you're pregnant with a character attack, you don't become unpregnant.”

For that reason, some in the party have harbored hope that he would speak out even more forcefully and even offer up himself as a witness as part of an exchange. To do so, the thinking goes, would show that he not only had nothing to hide but to flip the script on Trump.

“When he came out and said I won’t let you destroy my family, that was spot on. But it was weeks overdue,” said Philippe Reines, Clinton’s longtime communications adviser. “I’ve also been in favor of Biden saying: ‘You want me to testify, you want Hunter, you want my dog, great. We’ll do it along with Rudy & Mulvaney & Pompeo and their dogs.’”

“The real issue with Biden,” Reines concluded, “isn’t that he hasn’t had effective responses, it’s that it’s taken him weeks, sometimes months, to deliver them.”