As he bowed out of the race for president, Vice President Biden repeated a point that he'd been making all week — a point that hinted at what a flawed candidate he could have been.

"I don't believe, like some do, that it's naive to talk to Republicans," Biden said, as his wife, Jill, and President Obama stood with him. "I don't think we should look at Republicans as our enemies. They are our opposition; they're not our enemies."

As Fixer-in-Chief Chris Cillizza has pointed out, this was a none-too-subtle reference to Hillary Clinton. In what was supposed to be a light moment at last week's debate, Clinton responded to a question about the "enemies" she was proud to make by rattling off a list, ending in "the Republicans." Biden latched onto that line, and until the second he entered the Rose Garden, it was read as proof that he'd challenge Clinton.

The problem was that progressives — the people who'd be picking the nominee — did not agree with Biden. At all. If they agree on anything, it's that Obama's unifying message of 2008 was utterly unsuited to the challenges of Washington in 2009.

"[Obama] thought he could walk into Capitol Hill and the Oval Office and sit down with John Boehner and Mitch McConnell and the Republicans and say, ‘I can’t get it all. You can’t get it all. Let’s work out something that’s reasonable,’ because he’s a reasonable guy," Sen. Bernie Sanders (I-Vt.) told former top Obama strategist David Axelrod in an interview last month. "He’s a pretty rational guy. These guys never had any intention of doing [serious] negotiating and compromising, [and] I think it took the president too long to fully appreciate that.”

Sanders, who's surged from the fringes to become an iconic challenger to Clinton, spoke for millions of progressives who felt that Obama squandered political opportunities by assuming the best intentions from Republicans. The Obama years saw Republicans exploit that and pick off all but a rump of white, conservative Democrats.

To progressives, a pundit who asks where the compromisers have gone is not just naive; he or she is willfully ignorant. He can't even read the charts, kindly provided by political scientists, about how the decline of moderate Republicans and the extermination of Dixiecrats has made Congress almost completely partisan.

"The conditions under which Biden once did cross-party deals are entirely dead," says Steven Teles, a political scientist at John Hopkins University. "He does a distinct disservice to the public to pretend that we could have more cross-party cooperation if only we had 'leadership.' Unless Biden has a proposal to magically get Republicans to elect people like John Danforth and Bob Michel back into Congress, all the good bipartisan will in the world isn't going to bridge the gap between the two parties."

The danger for progressives was not just that Biden was wrong. It was that the last adherents to the "just get in a room and work it out" theory of politics were all pundits — the sort of pundits egging Biden into the race. It might not have mattered to the vote count, but if Biden intended to argue that he got along with Republicans and Hillary Clinton couldn't, he would have furthered a much-loathed theory.

"Biden is also the product of a time — he was first elec­ted to the Sen­ate in 1972 — when polit­ic­al lead­ers worked to­geth­er, when party voters al­lowed their lead­ers to bargain and when mem­bers of Con­gress lived in Wash­ing­ton and made friends on both sides of the polit­ic­al di­vide," wrote progressive blogger bete noire Ron Fournier after the Biden speech. "It wasn't per­fect, but it was in many ways bet­ter than now."

Progressives have actually warmed to candidates who believe something else — something best expressed in the old Bill Clinton campaign theme song. Yesterday's gone — don't you look back.