The insultapalooza that was the 2016 presidential election — wherein Donald Trump doled out emasculating nicknames to his opponents, attacked women for their looks, and mocked everyone from an American war hero and disabled journalist to a Gold Star family — is burned on the brains of Democrats.

That feature of the 2016 election, in fact, has set the parameters for what Democrats are demanding this go-around: a candidate who’s “tough enough” to take on Trump.

To that end, every candidate has insisted they are.

Joe Biden, Elizabeth Warren, Bernie Sanders, Kamala Harris and Beto O’Rourke have all auditioned their versions of toughness on the debate stage and in interviews.

Seth Moulton, an Iraq War veteran who has since departed the race, used those exact words back in July, insisting that Democrats ”need someone who’s tough enough to take on Trump.”

Amy Klobuchar, after weathering a frigid outdoor campaign launch in Minnesota, taunted the president: “I’m tough enough. I would have liked to see him sitting out here in the snow for an hour giving this speech.” Even mild-mannered, soft-spoken Pete Buttigieg has defended his toughness, saying “If we want to have a debate with him, or a fight over any number of things. ... (T)he fact that I was packing my bags for Afghanistan when he was filming season 7 of ‘Celebrity Apprentice,’ we could have that fight.”

And countless strategists and pundits have framed the election in similar terms as The Washington Post’s Jennifer Rubin: “(V)oters are trying to imagine the Democratic contenders on the stage next to Trump.”

But what if they don’t get that chance?

For some bizarre reason, people seem to be treating it as a foregone conclusion — and even an organizing principle around which campaigns and candidacies have been centered — that Trump will participate in general election debates, giving Democrats the showdown they’ve been dreaming of since January of 2017.

I’m here to burst their bubble. It ain’t happening. The likelihood that Trump submits himself to three-hour, televised sparring matches with the Democratic nominee, no matter who it is, is slim to none in my opinion.

Here’s why. For one, he doesn’t have to. It’s not required of presidential candidates, though perhaps it should be.

Numerous candidates have skipped primary debates, and some have even passed in the general. Lyndon B. Johnson refused to debate Barry Goldwater in 1964, and Richard Nixon wouldn’t participate in 1968 or 1972 debates.

For another, Trump has already shown a willingness to forego the tradition. Recall, back in January of 2016 he opted out of a Fox News Republican debate as retaliation for previous debate questions from Megyn Kelly he perceived as unfair. His campaign sent out a statement defending the move, saying, “Like running for office as an extremely successful person, this takes guts and it is the kind of mentality our country needs in order to Make America Great Again.”

There’s also the fact that he’s made much better use of other platforms to connect to voters, namely Twitter and his barnstorming rallies, where he is in total control and having what is essentially a one-way conversation with his base.

To be sure, ditching the debates would be an unequivocal sign of cowardice and fragility on Trump’s part. But, he’ll likely offer myriad excuses as to why he won’t participate, all of which complement his favorite themes: He’s sticking it to the media outlets that host and make money off of these televised events; he’s giving his supporters what they want; he’s president and his opponent isn’t.

It’s possible Trump can’t resist the allure of a big, splashy television spectacle, and maybe he’ll submit to one debate and then ceremoniously swear off the rest, claiming they’re “rigged” or “unfair to Trump.” But I’m skeptical that we’ll see him on stage with the Democratic nominee at all.

So Democrats might want to spend less time fantasizing about the moment when Warren expertly lectures Trump on the science of climate change, or when Biden challenges him to a jousting match at Medieval Times.

Instead, they should prepare themselves for the very real possibility that none of these candidates will ever get to prove they’re tough enough to take on Trump at a debate. I guess they’ll have to save their hand-to-hand combat for Twitter.

S.E. Cupp is the host of “S.E. Cupp Unfiltered” on CNN.