If you want to know who to blame for Donald Trump, they will argue, just feel the after-Bern:

Framing Sanders as a divisive party outsider who won’t accept defeat, the Biden campaign pointed to his bitter Democratic primary fight four years ago with his party nemesis, Hillary Clinton. That ended with a chaotic nominating convention and Donald Trump’s election months later.

Biden’s strategy capitalizes on Clinton’s successful effort to brand Sanders as more unlikable than Biden among women, who favored the former vice president by 12 percentage points during his 10-state romp Super Tuesday, according to exit poll averages. With the averages showing Sanders lost black voters by even more — 34 points — the Biden campaign also tangentially brought up race in bashing the Vermont senator.

“We can’t divide this party like we did last time to allow Trump to get reelected,” Biden campaign co-chairman Rep. Cedric Richmond, a member of the Congressional Black Caucus from Louisiana, told reporters on a conference call Wednesday.

“The fact that Senator Sanders is on TV today with negative attack ads and consistently saying the establishment is teaming against him, no, African American voters have made a conscious decision that we fought and we earned civil rights through blood, sweat and tears,” Richmond said. “And so as he rails against the establishment, I did not know that African Americans in the South were considered part of the establishment.” …

Biden’s deputy campaign manager, Kate Bedingfield, was quick to remind reporters of the past.

“We’ve seen unfortunately what kind of campaigns Bernie Sanders runs,” Bedingfield said. “We saw the impact that it had in 2016.”

By “dividing the party,” Biden’s campaign means running attack ads against Biden. Er, isn’t this a primary? Did Biden get elected to the Senate and the VP slot by playing beanbag?

That’s clever, but it’s also dishonest, and perhaps needlessly provocative. Sanders could have disrupted Clinton’s campaign and the convention in 2016 after losing to her in what looked like a process cooked by the DNC — but he didn’t. Sanders had an open invitation from the Green Party’s Jill Stein to replace her at the top of that ticket — and declined. In fact, weeks before the convention, Sanders appeared at a Hillary Clinton rally to explicitly endorse her and urge his followers to unite to defeat Donald Trump. ABC News covered the speech live at the time:

I have come here to make it as clear as possible as to why I am endorsing Hillary Clinton and why she must become our next president.

Sanders certainly didn’t delight in Hillary’s nomination, but he fulfilled the honorable requirement of supporting her candidacy. Sanders kept his ire focused on Trump from that point forward. If his supporters didn’t feel any enthusiasm for Hillary, that might explain a lot about her loss, but that wasn’t Bernie’s fault. Hillary Clinton lost not because of the arguments against her in the primary, but because she’s a terrible candidate. They must be worried that Joe Biden’s turning out to be just as bad.

This is essentially a conspiracy theory Team Biden is peddling, and it’s a rather stupid one, strategically speaking. Democrats were already heading into a battle at the convention between the Bernie wing and everyone else because the Bernie wing feels like they ponied up in 2016 and it’s now their turn. If they lose on a first-ballot majority to Biden, they’ll be angry enough as it is. But if the new party-establishment narrative is that Bernie Sanders undermined Hillary to get Trump elected, the Bernie Bros will absolutely revolt in Milwaukee, and this time they will split the party. In fact, it’s almost impossible to see what Team Biden hopes to get out of this accusation other than a massive internecine fight that will split their already-fragile party into shreds.

As Republicans, all we can do is point out this extremely nearsighted strategy for what it is, and … pass the popcorn. Milwaukee is going to be spectacular.