What if President Joe Biden had held on to the Democratic nomination? I kept trying to imagine that alternate timeline (which would make for the dullest Marvel multiverse movie ever) as I wandered the Democratic National Convention this week. Certainly the merchandise would have been better: the unimaginative, hastily created Kamala Harris buttons made me wonder what they’d done with all the discarded Biden stuff. But in every other respect that alternate-reality convention would have been a grimmer affair.

Some speakers would not have appeared at all. Others would surely have delivered different lines, and their very presences would have delivered different messages, too. I doubt former President Bill Clinton, his steps now slower and his voice even huskier, would have dwelled as he did on his own age, wondering how many more conventions he might be able attend (his first was in 1972) and noting that he just turned 78. “And I’m still not quite as old as Donald Trump,” he added. That was a laugh line; no one would have been laughing if Joe Biden, aged 81, was still the nominee. 

Former President Barack Obama, out of office for almost eight years but still just 63, would have been another damaging point of comparison, with his penetrating speech and quicksilver delivery. Speeches by formidable, ascendant Democrats, such as Governor Wes Moore of Maryland, would have had the delegates in that other timeline yearning to be in this one instead. As it was, Vice-President Kamala Harris, when she delivered her down-to-business, yeomanlike speech in the hall on Thursday night, seemed to beam down from high noon, at a kind of equipoise between the rising political stars and the setting ones. 

This points up a huge long-term challenge to the Republican Party, regardless of who wins this year’s election. Donald Trump’s politics of disruption, twinned with his I-alone-can-fix-it branding, has been core to his political success, appealing to Americans’ appetite for change. But as the Republican convention in Milwaukee showed, his influence has blanked out the party’s past and made its future something of a mystery, particularly given the unsteady performance so far of his running mate, Senator J.D. Vance of Ohio, a relative political newcomer. The only other living Republican president, George W. Bush, did not even attend that convention, nor did many other former Republican officials, including Mr Trump’s former vice-president, Mike Pence. 

Asa Hutchinson, a former Republican governor of Arkansas and former presidential candidate (and, as a congressman, House manager during the impeachment of Mr Clinton), was in Chicago as a political analyst for Scripps News. He told me that at both conventions delegates were energised and seemed unified. “But then you look a little bit deeper,” he went on, “and the fact is that at the Republican convention, it was unity by self-exclusion that, you know, so many were not there and were not welcome. And here, the fact that you do have former presidents sends a message of true unity, and that they have broad support for Kamala Harris.”

The Democrats’ ex-presidents also seemed to be supplying critical ballast as Ms Harris and her running-mate, Governor Tim Walz of Minnesota, tack back towards the political centre. The party’s left in recent years had become, to different degrees, disdainful of Mr Clinton and Mr Obama. But, to the extent Ms Harris is clarifying her policy positions at all, a more incrementalist, less revolutionary Democratic Party is coming back into focus. In Chicago the delegates heard a lot about Ms Harris’s experience in fighting crime as a prosecutor. The only “privilege” she mentioned in her speech was that of being an American. Indeed, words that just a couple of years ago seemed to be on every Democratic officials’ lips, such as “equity”, seemed to have vanished from the party lexicon. So, at least for long stretches of the convention, did the name “Biden”. When Pete Buttigieg strode onto the podium, he was introduced as the former mayor of South Bend, Indiana. Is it only in some other timeline that he currently serves as Mr Biden’s secretary of transport?

All of this must be excruciating for Mr Biden, who is not even a former president yet. Still, as I write in Lexington this week, no Democratic politician has a greater need for Ms Harris to win. 

Many of you were good enough to write in last week after I argued for restoring a greater role in nominations for party professionals, and most of you agreed. Do you agree the Republican Party has jettisoned much of its history—and if so do you think that’s a drawback or an advantage? Write to me at jbennet@economist.com.  

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