The lingering bad blood between the Sanders and Clinton camps then spilled more fully into public view Monday by way of a Politico story headlined “Ex-Clinton Staffers Slam Sanders Over Private Jet Flights,” in which former Clinton staffers complained that the campaign had to pay to fly Sanders on private jets while he was stumping for Clinton in the general election. Much of the sniping was done under cover of anonymity, but the harshest words were on the record. “I’m not shocked that while thousands of volunteers braved the heat and cold to knock on doors until their fingers bled in a desperate effort to stop Donald Trump, his Royal Majesty King Bernie Sanders would only deign to leave his plush D.C. office or his brand new second home on the lake if he was flown around on a cushy private jet like a billionaire master of the universe,” said Zac Petkanas, who led Hillary’s rapid response team in 2016. Michael Briggs, Sanders’ 2016 campaign spokesman, fired back, calling Clinton’s team “total ingrates” and “some of the biggest assholes in American politics.”

The insult-slinging was ostensibly about private jets, but in reality it was a proxy for the larger debate that continues to bubble up inside the Beltway in Year 3 of Donald Trump’s presidency—namely, how much Sanders’ primary challenge damaged Clinton’s candidacy and whether he subsequently did all he could to heal the intraparty wounds before the general election. The fact that Monday’s spat was about Sanders’ mode of travel to Clinton rallies illustrates how unproductive this feud is. It’s about whether Sanders did enoughto help the first female nominee of a major party in U.S. history—not whether he helped her at all. Likewise, it calls to mind the running debate over Bernie Bros, who simultaneously exist and don’t exist in the numbers Sanders’ critics suggest: Did Bernie do enough to rein in the worst impulses of his most combative fans, and is he doing enough now? As narrow as these rifts are, they’re unlikely to ever be bridged by the two entrenched sides.

The good news for Sanders is that it’s not entirely clear that the festering 2016 resentment matters outside the Beltway. His favorability rating within the Democratic rank and file suggests the vast majority of primary voters have either forgiven, forgotten, or never noticed the rift in the first place. In the Morning Consult poll, for example, 75 percent of Democratic voters said they had a favorable opinion of Sanders, while just 15 percent said they had an unfavorable one. Those numbers are nearly as good as Biden’s (76 percent to 12 percent) and farbetter than every other potential rival, none of whom have faced the same kind of he’s-not-even-technically-a-Democrat complaints that get lobbed at Sanders from the party faithful.

If the old Clinton and Sanders camps continue to relitigate those old grievances, however, the squabbles could complicate Sanders’ attempts to defend himself from the more specific criticisms leveled at his first presidential campaign, which include the alleged mistreatment of female staffers and his lackluster appeals to black voters, particularly in the early nominating contests back when his leadership team was predominantly white. Sanders has taken steps to address both—he apologized to his female campaign staffers publicly, and he’s now more explicitly drawing a connection between economic inequality and racial inequality than he did in 2016—but the complaints will almost certainly re-emerge in a primary where gender, race, and identity are dominant themes. Sanders may have to lug his 2016 baggage with him into 2020, especially if a candidate of color and/or a woman emerges as his most direct challenger. The question, though, is whether his campaign will have so much momentum that he won’t feel the weight of it.

• 2020 Campaign
• Bernie Sanders
• Democrats
• Hillary Clinton