You, Bernie Sanders, are no Ted Kennedy. (Why that's good for Hillary.)

Bernie Sanders formally endorsed Hillary Clinton Tuesday, avoiding a repeat of the disastrous 1980 Democratic presidential campaign.

Bernie Sanders is no Ted Kennedy. For Hillary Clinton, that must come as a relief. 

We’re talking about political effect here, not ideology. Senator Sanders is a lion of the liberal left, as was Senator Kennedy, after all.

But Sanders has swallowed his pride after a bruising primary campaign and endorsed his party’s presidential choice well before the Democratic National Convention. That’s something Kennedy didn’t do when he ran against President Jimmy Carter in 1980. The result was a split in the party that probably cost Democrats at the polls that November.

Sanders’s moment of truth and reconciliation came Tuesday, when he stood on stage with Mrs. Clinton at a high school in Portsmouth, N.H.

“I have come here to make it as clear as possible why I am endorsing Hillary Clinton, and why she must become our next president,” said Sanders at the joint rally. “Secretary Clinton has won the Democratic nomination, and I congratulate her for that.”

To a certain extent, this endorsement is just recognition of reality. Sanders lost. He’s acknowledging that fact.

But Clinton won weeks ago. It’s taken Sanders some time to step up and publicly say he’ll support the woman who defeated him.

Perhaps Sanders, elated by months of electoral relevance, needed time to adjust to suddenly diminished status. Perhaps he was just dragging his feet to maintain leverage over Clinton’s campaign. 

In that latter effort he was pretty successful: Sanders got at least “80 percent” of what he wanted in the Democratic platform, according to his policy director Warren Gunnels. That includes support for a $15 per hour minimum wage, carbon pricing, tougher regulations on fracking, and Clinton support for a public option in Obamacare.

“It’s true that the platform is non-binding and therefore that this victory is of limited utility, but moving a political party in an ideological direction takes time and establishing markers in the platform is one way of demonstrating that there’s a consensus for your priorities,” writes Martin Longman today at the Washington Monthly.

Why did Clinton accede to this? She wants party unity and a happy Sanders camp. She doesn’t want a Ted Kennedy situation, where an angry loser split Democratic true believers and helped an incumbent president lose.

Like Sanders, Kennedy lost at the end of a long, tough primary campaign. It was 1980, and the Kennedy scion had decided to challenge Carter following the latter’s so-called “malaise speech,” which seemed to blame voters’ attitudes for some of the nation’s problems, according to Kennedy’s memoir “True Compass.” Kennedy hadn’t gotten along well with Carter to that point; he felt the nation needed a real Democrat in the race.

But Kennedy didn’t concede prior to the Democratic National Convention, held that year in New York. Carter’s margin of victory wasn’t overwhelming, and Kennedy thought he might still win if he could unbind delegates at the convention and get them to vote their conscience.

That didn’t work. (The #NeverTrump effort to similarly unbind GOP delegates probably isn’t going to be any more successful, FYI.) On the convention’s second day, Kennedy finally backed Carter in a speech. But the address – the famous “the cause endures” speech – was more a rallying cry for liberals than a call for unity. Then came the handshake debacle.

Invited onstage after Carter’s climactic nomination, Kennedy shook Carter’s hand. To the press, it looked perfunctory. That’s how they played it in reports.

“I must have shaken hands with him two or three times. But I didn’t elevate his hand; he made no effort to elevate mine!” said Kennedy in a 2005 oral history for the University of Virginia’s Miller Center. “I thought it was proper enough. But as the press pointed out, there wouldn’t be any pictures of me raising his hand, which I had not expected to do, but if he had raised both of our hands, I would not have resisted it, certainly.” 

Carter lost to Ronald Reagan that November. Many Carter supporters blamed Kennedy for splitting the party in two. Carter himself remains angry with Kennedy for not helping more throughout his presidency; in 2010 he told an interviewer he thinks Kennedy blocked a Carter health reform bill to deprive him of a legislative triumph. 

For his part, Kennedy thought Reagan was beatable. But Carter fumbled the debates, in his view, and never recovered from the Iranian hostage situation and various missteps.

“I don’t think Carter could dig his way out of the other kinds of problems he had,” Kennedy said in 2005.

Will Clinton and Sanders similarly be sniping at each other in years to come over a political relationship that turned dysfunctional? That may depend on the outcome of the election. Sanders supporters are still suspicious that Clinton is a moderate who doesn’t really back their priorities. The Clinton camp sees Sanders as a dreamer who hasn’t entirely woken up to the existential crisis that is Donald Trump.

But victory would be a great salve. Clinton is heading into a convention season with at least nominal party unity and a poll lead that has proved durable, so far.

“We are joining forces to defeat Donald Trump,” said Clinton on Tuesday at the New Hampshire unity event.