Joe Biden is a lot of fun as a candidate. He’s funny, smart, big-hearted, passionate—and, most importantly, wildly undisciplined compared with other top-level politicians. He’s liable to say what comes into his mind, and that’s way better than the typical cautious, canned stump speaker.

So it’s good news for campaign-watchers that Biden, now 76 years old, is reportedly leaning toward entering the race within the next few weeks.

But those traits are also why somebody really should convince him to stay on the sidelines.

On paper, Biden is a top candidate—perhaps even deserving his current front-runner status in polls. He has decades of public service under his belt, compiling a strong liberal record with crossover appeal among moderate voters. He almost certainly will have the best grasp of foreign policy in the 2020 field of candidates. He is nationally known, and generally well-liked and respected among voters and party activists alike.

But in the spotlight of a Presidential campaign, Biden’s loose lips and guileless manner will inevitably reveal outmoded attitudes that just won’t fly with today’s Democratic Party activists.

Maybe it will be a racial gaffe along the lines of him calling Barack Obama “the first African-American who is articulate and bright and clean” in 2007; or saying in 2006 that in Delaware “you cannot go to a 7-11 or Dunkin’ Donuts unless you have an Indian accent.”

Perhaps it will be demeaning treatment toward women, a pattern significant enough to have achieved meme status.

Those who know Biden defend him as a genuine good guy, whose occasional flubs are misinterpreted or blown out of proportion. But even they concede that those “Uncle Joe” moments are unlikely to stop—just this past May he referred to women benefiting from a training program as “from the hood”—and that they are likely to land him in trouble with primary voters.

In fact, several political pros who worked or volunteered for Biden’s 2008 campaign have told me they are unlikely to do so this cycle—in part because they know the embarrassments are coming.

“It definitely is going to happen,” one says. How badly it hurts him and his legacy “depends on the time and circumstances,” this operative adds.

A New Party

To be fair, Biden is impressively enlightened for someone who came out of the old-boy’s Democratic political world of the 1970s and ‘80s. Locker-room talk, and attitudes, were pervasive then, especially in the U.S. Senate. Biden, though often more conservative on policy than his northeastern Democratic pals, including Ted Kennedy of Massachusetts and Chris Dodd of Connecticut, was arguably ahead of them at times on progressive attitudes toward women and the LGBTQ community.

Nevertheless, speaking off-the-cuff he still often sounds like… well, like a 76-year-old Uncle Joe.

Last March, at an anti-violence rally, Biden said of Trump’s notorious “grab ‘em by the pussy” remarks, that “if we were in high school, I’d take him behind the gym and beat the hell out of him.” He went on to say that in locker rooms he’s been in, “any guy that talked that way was usually the fattest, ugliest SOB in the room.”

Responding to sexual harassment with masculinity-fueled threats of counter-violence is not exactly what the #MeToo movement preaches—let alone spreading the misconception that sexual aggressors are characteristically unattractive, or frustrated by sexual rejection. Despite Biden’s strong record, including the Violence Against Women Act, “he doesn’t understand rape culture,”wrote a Huffington Post campus editor-at-large after that speech.

Biden later said he regretted the comments—but only because he shouldn’t have stooped to Trump’s trash-talking level.

Just a few years ago, those kinds of off-the-mark comments would likely not have been politically damaging. Perhaps some activists would mutter complaints, and maybe some Republicans might feign horror, but the bulk of Democratic party activists have been accustomed to the gap between older elected officials and inclusive attitudes taught in contemporary schools and embedded in modern culture.

It's hard to overstate how quickly that has changed. Democratic activism is now dominated by working-age women and minorities who have surpassed the limits of their patience. Some of it is a reaction to Trump, certainly, but they aren’t willing to put up with backward attitudes from anyone anymore.

Consider the online backlash against Nancy Pelosi when she botched a softball Black Lives Matter question last Friday, on an MSNBC town hall.

Or, look at what happened to Congressman—correction, former Congressman—Michael Capuano of Somerville a few months ago.

Challenged by Ayanna Pressley in the Democratic primary, Capuano seemed confident in his progressive credentials. But Pressley was fluent in the new language of intersectionality; whereas Capuano dismissed it as new jargon for the same old issues.

When Capuano said that quarterback Colin Kaepernick should have raised issues of discrimination and police violence “in a less divisive way” than kneeling during the National Anthem, the tide turned decisively against him, among young progressives and African-Americans. And, unlike past midterm elections, those voters came out to vote in large numbers.

Capuano, like Biden, assumed that his long, strong record on the issues inoculated him against such criticisms. Even after losing, he doesn’t seem to grasp where he went wrong—blaming his loss instead on voter anger.

Democrats aren’t voting angry in primaries; if anything, in 2018 they took a measured approach to elevating strong general-election candidates. They’re just not putting up with anyone who hasn’t bothered to transition into the 21st century’s basic guidelines for treating one another.

If you’re not as woke as a typical Ariana Grande song, you probably have no business asking for Democratic votes. Capuano found that out. Biden is about to.

In The Spotlight

Within the Democratic party, Biden has been treated with kid gloves for a very long time. In part, because he is genuinely liked and respected, but also because he’s been no threat to anybody.

The last time he competed in an election against fellow Democrats—the only time, in decades—was his ill-fated 2008 Presidential campaign. He never reached 5 percent in national polls, and dropped out after getting fewer than 1% of caucus votes in Iowa. He wasn’t worth picking on, and was left alone.

Since then, Biden has received the deference you would expect from party activists and leaders, for a Vice President and party elder, as well as a close friend of Democratic demigod Barack Obama.

That won’t last long, if he enters the 2020 Presidential campaign with his current front-runner polling status.

Every move and utterance of his will be recorded and studied. There will be several women in the Democratic field, and a few black and Hispanic candidates, all ready to pounce on any wrong move—not to mention the other white men, seeking to prove their woke credentials.

And he’ll be forced to address sensitive topics, whether he wants to or not. Primary voters are already looking for elucidation on his long public record. One hot one he’s never satisfactorily addressed is his strong support for the 1994 crime bill, now seen as exacerbating racial criminal-justice disparities.

If Biden is taking all this more seriously than Capuano did, there is no evidence of it yet. A more disciplined, rigorous campaigner might be able to tamp down his out-of-touch rhetoric and stay out of trouble. That’s not Biden; never has been, and it’s hard to imagine him changing now. It should be fun to watch, while it lasts, but it won’t end well.