President Jimmy Carter shakes hands with former Republican presidential candidate Ronald Reagan after debating in the Cleveland Music Hall in 1980.Madeline Drexler / AP

HEMPSTEAD, N.Y.—Before this week’s first presidential debate, it was common for Donald Trump’s television surrogates to predict it would echo the sole 1980 encounter between Jimmy Carter and Ronald Reagan.

It turned out, to borrow from another famous debate moment, Donald Trump was no Ronald Reagan.

On the surface, the analogy appeared reasonable. Like Hillary Clinton today, Carter in 1980 bet most of his chips on personally disqualifying Reagan. Carter painted his opponent as unqualified, ill-informed, extreme, and dangerous—an aging entertainer who might trigger a nuclear war through ignorance and belligerence.

For months, enough voters feared Carter might be right to keep him close in the polls, despite enormous dissatisfaction with his job performance. But when Reagan in the debate presented himself as composed, reasonable, and genial (swatting away even accurate Carter recitations of his most outrageous earlier statements with a jaunty “There you go again”) the doubts softened, Carter’s support crumbled, and the Gipper rolled to a landslide.

Trump’s television chorus confidently predicted a repeat. Trump, they promised, would show himself as a man that Americans could easily envision representing them to the world, managing the military, and breaking gridlock in Congress. More than a few Democrats feared they might be right. The Clinton campaign had portrayed Trump so ominously that he might have discredited the picture if he had just made it through 90 minutes seeming polite and reasonable.

In the end, Democrats had nothing to fear. The Trump at Hofstra was, for better or worse, the vintage primary-edition version, not the restrained model he’s mostly displayed in recent weeks. Rather than pivoting to some “new Trump,” he spent 90 minutes reaffirming the qualities that have made him so polarizing—strong and iconoclastic to his supporters, volatile, mendacious, ill-informed and bigoted to his doubters. He projected strength (particularly when he prosecuted Clinton on trade) but was also rude, undisciplined, and frequently flailing on substance (see his self-contradicting answer on nuclear weapons). It’s difficult to imagine any voter who turned on the debate dubious that Trump was qualified to be president left the couch convinced that he was. As one top Republican strategist told me afterwards, “Trump is who we thought he was.”

That verdict seemed even more apt when Trump almost immediately escalated a new dispute with the former Miss Universe, Alicia Machado, who Clinton had raised in the debate to accuse him of disrespecting women. Trump’s worst general-election moments have come when he has ignored the old political adage that candidates should never get in an argument with anyone who isn’t on the ballot: His polls have skidded most around his feud with the Muslim American Khan family and his attacks on the Indiana-born Hispanic judge Gonzalo Curiel. Heedless of that history, Trump responded with confrontation—not contrition—after Machado said he had belittled and humiliated her when she gained weight following her victory in the pageant.

The spectacle of a man possibly six weeks from election as commander in chief badgering a former beauty queen probably did little to reassure voters who worry that Trump might be too volatile and vindictive to trust with nuclear weapons. And the roughly three-fifths of Americans who have consistently told pollsters they consider Trump racially biased likely noticed that for the third time in months, he was disparaging an ordinary citizen whose ethnic heritage and facial complexion did not match his own.

These personal doubts largely explain why the Republican leadership class has fractured over Trump’s candidacy more than any other in modern times, even Barry Goldwater’s doomed race in 1964. Though rank-and-file Republican voters have mostly rallied around Trump, he continues to face unprecedented defections from Republican leaders and institutions. The Wall Street Journal for instance, recently reported that not a single CEO in the Fortune 100, an ordinarily Republican-leaning group, has donated money to him. John Warner, the former Republican chair of the Senate Armed Services Committee, this week endorsed Clinton, joining dozens of former GOP national security leaders who have either rejected Trump or backed the Democrat. Former President George H.W. Bush hasn’t denied reports he’s voting for Clinton. And the Arizona Republic newspaper, which had never endorsed a Democrat in its 126-year history, this week joined such other staunchly Republican outlets as the Cincinnati Enquirer (which hadn’t endorsed a Democrat since 1916) and Dallas Morning News (not since 1940) in picking Clinton.

Some of that resistance flows from policy disputes, particularly Trump’s rejection of the historic internationalist GOP consensus on trade and foreign alliances. But this opposition springs primarily from skepticism about Trump’s personal fitness. In its editorial this week, the Arizona Republic concluded Trump suffers from “deep character flaws”; displays “a stunning lack of human decency, empathy and respect” and would threaten national security with “reckless” behavior and rhetoric. John Warner dismissed him more succinctly: “You don't pull up a quick text like National Security for Dummies.”

One of Clinton’s biggest gambles has been to focus far more on personally disqualifying Trump than on trying to critique his agenda or even to tout her own. She’ll need a more positive message to energize elements of the modern Democratic “coalition of the ascendant,” particularly Millennials and Latinos, who haven’t shown high interest in voting despite their distaste for Trump. But the bigger risk of Clinton’s approach was that Trump might discredit it with a reasonable and competent performance at the debates. In a campaign that still exposes her to many risks, that’s one thing Clinton hasn’t yet needed to fear.

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