For Hillary Clinton, the most politically damaging aspect of her recent health scare is not any new revelation but the reemergence of an old pattern.
The image of her buckling at the knees Sunday pushed doubts about her personal well-being from the crazy realm of conspiracy mongering squarely into the mainstream of serious discussion.
Making things much worse, though, was her campaign's handling of the episode — the delays, the half-explanations, the grudging trickle of information — which played to some deep concerns going back to Clinton's White House days and controversies over openness and candor.
Far and away the biggest impediment standing between Clinton and the White House is the fact a great many voters, including some with every intention of voting for the former first lady and secretary of State, simply do not trust her.
The events Sunday did nothing to reassure them.
Rather, they brought a rush of memories for those around the last two decades — of parsed words, of legal and ethical controversies, of tiptoeing to the edge of accepted rules — that are symptomatic of the political ailment known as Clinton fatigue.
For Republicans and those who hate the presidential front-runner, Sunday's episode merely ratified their deep-seated contempt. It suggested that Internet-fueled rumors about a physical and mental breakdown, though fanned by rival Donald Trump and his backers and seemingly far-fetched, need to at least be addressed.
For Democrats, it was maddeningly frustrating.
"They continually undercut their ability to get to the high ground," said Paul Maslin, a Democratic pollster who supports Clinton but worries she might squander her advantages over Trump and lose in November. "Whether it's on outrageous statements, whether it's national security, whether, in this case, it's full disclosure if you want to hit Trump on his medical records.… This certainly isn't helpful."
David Axelrod, the impresario behind President Obama's election and hardly a fan of Trump, offered his astringent commentary on Twitter.
"Antibiotics can take care of pneumonia," he said, referring to Clinton's belatedly announced diagnosis. "What's the cure for an unhealthy penchant for privacy that repeatedly creates unnecessary problems?"
A spokeswoman for Clinton, Jennifer Palmieri, responded with a mea culpa of sorts.
"We could have done better yesterday," she tweeted, "but it is a fact that public knows more about [Clinton] than any nominee in history."
Calling in Monday night to CNN, the candidate said much the same thing.
"If we weren't fast enough … we take responsibility for that, but the information is out there," said Clinton, who, on doctor's orders, rested away from public view and skipped a fundraising swing through California. "You can't say the same thing about Donald Trump.… We know the least about Donald Trump of any candidate in recent American history."
The semi-apology was part of a daylong effort at containment and damage control.
Earlier, the Clinton campaign announced it would soon release additional information about the candidate's medical condition, going beyond a two-page letter attesting to her good health that her personal physician issued in July 2015. Aides insisted pneumonia was her only health issue.
"We're going to be releasing that to further put to rest any lingering concerns about what you saw yesterday," Brian Fallon, a Clinton spokesman, said on MSNBC.
For his part, Trump has issued a vague and hyperbolic four paragraphs from his doctor declaring the Manhattan businessman, if elected, would "unequivocally … be the healthiest individual ever elected to the presidency." It turned out the doctor dashed off the letter in five minutes.
On Monday, the Republican nominee was uncharacteristically restrained about Clinton's malady, saying he had recently undergone a physical and would announce the results — perhaps fittingly for the reality TV star-turned-candidate — on Thursday's episode of the syndicated show hosted by cardiologist Mehmet Oz.
Clinton supporters have asserted with increased vehemence that she has been held to a higher standard than Trump, who routinely dissembles about his positions and has been considerably less than transparent — refusing, for instance, to release his tax returns as presidential nominees have routinely done.
But those facts have been widely and repeatedly reported, contributing to the highly negative image most voters have of Trump and pushing some who otherwise might never vote for Clinton to consider the Democrat as an alternative.
"What they're trying to figure out is if they can live with Hillary Clinton for the next four years," said Peter Hart, a veteran Democratic pollster who has conducted numerous focus groups of voters around the country and often found her trustworthiness to be the greatest impediment.
He said the events Sunday, which might have engendered sympathy, may instead raise fresh doubts.
Clinton took ill suddenly while attending a New York ceremony marking the 15th anniversary of the Sept. 11 terrorist attacks. Reporters allowed to follow the candidate noticed her abrupt departure, but the campaign refused to answer questions about where she was going or why; in a breach of the usual protocol, her motorcade left without them.
She emerged about two hours later from her daughter Chelsea's Manhattan apartment, looking chipper and saying she felt fine but refusing to offer any details about her affliction.
The campaign initially told reporters Clinton had suffered from heat exhaustion. It was only after video surfaced of Clinton staggering into her van, with Secret Service agents propping her up, that the campaign released a doctor's note, explaining she had been diagnosed last week with pneumonia. (By Monday afternoon, the scene had been viewed more than 2.5 million times on YouTube.)
"I think that in retrospect we could have handled it better, in terms of providing more information more quickly," Fallon said on MSNBC.
To many frustrated Clinton supporters, that was an understatement and result of a self-defeating tendency, embodied by the controversy over her home email server, to let an obsession with personal privacy cloud her judgment.
"The big irony, of course, is that her email server was supposed to protect her privacy and now it turns out to be her worst enemy," said a former Clinton White House official who spoke on the condition of anonymity to preserve his relationship with Bill and Hillary Clinton.
Opinions of Trump and Hillary Clinton, two of the least-popular candidates in presidential campaign history, are firmly held by most of the electorate. So it is doubtful what happened Sunday will greatly shake up the race.
But it does raise another hurdle for the Democrat among undecided voters and elevate the already high stakes for the first presidential debate in less than two weeks.
President Reagan, who was 73 at the time, stirred doubts about his mental and physical capacity when he delivered a meandering performance in the first debate of his 1984 reelection campaign. He immediately dispelled those concerns with a winning performance two weeks later.
A similarly strong showing by Clinton could quickly reassure voters she is of sound body and mind. But she has her work cut out convincing skeptics she is someone they can trust.
5:35 p.m.: This article was updated with Clinton's comments to CNN.