It is hard to overstate just how much President Trump repels young voters.

“No recent president has ever been more hated by young people,” Samuel Abrams, a professor of political science at Sarah Lawrence College and a fellow at the American Enterprise Institute, said in an interview. “This generational opposition casts a very dark shadow on the future of the Republican Party.”

Reams of survey data confirm Trump’s unpopularity with young adults.

According to the latest Harvard Youth Poll, 60 percent of likely voters under 30 support Joe Biden in the presidential race, compared to just 27 percent for Trump. In a new Politico/Morning Consult poll of voters between 18 and 23, the results are similarly lopsided: 51 percent for Biden vs. 25 percent for Trump. An NBC News analysis of responses from 2,000 voters underscores the poor regard in which Trump is held: “Among the youngest cohort, Gen Z, 59 percent view the president negatively, compared to just 27 percent who view him positively. That’s a net negative rating of minus-32 points.”

It isn’t only Trump that young voters shrink from. It’s the Republican Party, too. Within the circle of self-identified Republicans, both young and old, the president enjoys enthusiastic support. But that circle is shrinking. In the four years that he has dominated American politics, Trump has recast the GOP in his own image. It may not recover from that blow for a generation to come.

Since 2016, “there has been absolutely no Republican growth whatsoever,” said Abrams. “Trump has his charged-up core of supporters, but he’s missed a phenomenal opportunity to actually build a meaningful coalition.” Presidents almost always strive to expand their electoral base, but Trump “made absolutely no effort to grow the Republican Party. He could have expanded the base. He chose not to.”

That conclusion is borne out by party registration numbers. Among Gen-Zers enrolling as voters, says Abrams, 50 percent register as Democrats, 25 percent as Republicans, and 25 percent as independent. These voters are forming their first political impressions, which tend to harden as voters grow older. They are coming of age at a time when “Republican” equals “Trump” — and by a 3-1 ratio, they are refusing to register as Republicans. Most will never look back.

To be sure, the GOP has done poorly among the youngest voters in recent elections. “I don’t see how a young American can vote for a Democrat,” a frustrated Mitt Romney told a student audience during his 2012 campaign. “You guys ought to be out working like crazy for me and for [Republicans] like me.” Alas for Romney, he lost to Barack Obama among 18- to 29-year-olds by a 23-point margin.

Nonetheless, it is a fallacy that young voters always tilt to the left. Trump apologists may try to convince themselves that no Republican nominee ever stands a chance with voters in their teens or 20s, but it isn’t true. In the 2000 election between George W. Bush and Al Gore, for example, voters under 25 were evenly split. In 1988, George H.W. Bush handily defeated Michael Dukakis among young voters, 53-47.

Most impressive, however, was Ronald Reagan’s extraordinary success among young voters, 61 percent of whom voted for him when he ran for reelection in 1984. Reagan was beloved by young voters, with whom he forged what the Miami Herad called “one of the strongest bonds in American politics.” Shortly before the 1984 election, Time magazine reported that “Reagan consistently runs strongest not among his fellow senior citizens or even middle-aged voters, [but] among those who are 18 to 24 years old… . Members of this age group are registering as Republicans, rather than as Democrats or independents, by ratios of 2-to-1 and 3-to-1.” Under Trump, those numbers have reversed.

In a contest with Obama, who was exceptionally popular with young voters, Romney (like John McCain in 2008) had no chance of prevailing. But Biden generates none of Obama’s buzz. Generation Z voters show little passion for Biden; according to Harvard’s Youth Poll, only 30 percent of young Biden supporters are enthusiastic about his candidacy. If Trump were a normal Republican, a race against Biden could have been a great window of opportunity to attract young, new voters to the GOP.

But Trump — vulgar, narcissistic, paranoid, crude, indecent — is anything but normal. He is the anti-Reagan: By and large, young Americans detest him, and will have nothing to do with his party. Not now, and probably not ever.

(Jeff Jacoby is a columnist for The Boston Globe).