Mr. Trump offers dislocated white men convenient scapegoats — Mexicans, Muslims, trade policies, political correctness — and promises to return those men to their rightful place in society. With his string of model or actress wives, his beautiful pageant girls on competitive parade and his vulgar displays of wealth, Mr. Trump embodies a fantasy of masculine power reclaimed. Mrs. Clinton, an unapologetically ambitious woman running to take the place of a trailblazing, successful black man, symbolizes all the ways in which America has moved on — and in her promises to help alienated men catch up is the implicit expectation that they, too, must change.

It’s tempting to write off people who refuse to evolve, especially if their candidate loses the election. But the ugliness of the Trump campaign is evidence of how white men existing in their own shrinking universe can be a real threat. For women, greater educational achievements, a lifetime in the work force and delayed marriage and childbearing mean our lives are more expansive and outward-looking than ever before. Working-class white men, though, have seen many of their connections to society severed — unions decimated, jobs lost, families split apart or never formed at all — decreasing their social status and leaving them increasingly isolated. That many white men are struggling surely contributes to Mr. Trump’s popularity, but the driving force of this election is not money — the median household income of Trump primary voters was about $72,000 a year, $16,000 more than the national median household income. It’s power, and fury at watching it wane.

White men have always seen the world differently than women and minorities, but the norms and views of white male America are now being cast as marginal and, sometimes, delusional. This is a stunning shift.

The differences in how men and women interpret the same information is evident in responses to Mr. Trump. As of early October, more than half of men believed that Mr. Trump respected women either “some” or “a lot.” That poll was conducted after the Republican nominee was on record calling women pigs and dogs, commenting about his own daughter’s sex appeal, and labeling a former Miss Universe, Alicia Machado, “Miss Eating Machine.” At the same time, nearly two-thirds of women said that Mr. Trump didn’t respect them. While more men now agree that Mr. Trump doesn’t respect women after the vulgar “Access Hollywood” tape came to light, more than four in 10 continue to say that Mr. Trump respects us. Which really makes you wonder what these men think respecting women looks like.

The men feminism left behind pose a threat to the country as a whole. They are armed with their own facts and heaps of resentment, and one electoral loss, even a big one, will not mean widespread defeat. Other Republican candidates are no doubt observing Mr. Trump’s rabid fan base and seeing a winning strategy for smaller races in certain conservative, homogeneous locales.

In the last weeks of this ugly campaign, Mr. Trump has continued to talk about a rigged election and hint that he may not accept the results if he loses on Tuesday. While he is emboldening his followers to rage in the face of an electoral loss, Mrs. Clinton and her fellow Democrats are working to expand the ranks of women in elected office, giving the face of American power an even more extreme (and feminine) makeover. Democrats have been far better than Republicans at running diverse candidates, and if those candidates do well, the Senate could be almost a quarter female — a record high. Half of the candidates in the most competitive races to flip congressional seats from red to blue are women. Mrs. Clinton herself has reasserted her feminist identity, sometimes covertly: At both the Democratic National Convention and the final debate, she wore a crisp white suit, a sartorial homage to the white-clad suffragists whose victories are recent enough that a small number of women who were born before women could legally cast a ballot will be voting for Mrs. Clinton on Tuesday.

It’s impossible to say whether a female president would help normalize female power and heal some of the rifts made visible by this election, or if she would so enrage many men that these gaps will only cleave wider. What is clear now is that this is the great unfinished business of the feminist project, a long-fermenting suspicion brought into bright light by this election: Expanding roles and opportunities for women cannot usher in full gender equality unless men change.