Memo to Hillary Clinton: if there is anything we don’t know about your state of health, including what happened exactly on Sunday morning, do not obfuscate or dissemble. Get it all out now.

We know where slipping and sliding and pretending nothing is awry gets you. The mess over the private email server you used while Secretary of State wouldn’t still be the number one preoccupation of your political enemies if only you hadn’t been so reluctant to admit your errors at the outset.

It seemed awfully like you might be doing something similar when you emerged from your daughter’s apartment building at noon on Sunday and declared breezily that it was a “beautiful day in New York”. Trying to distract the media from the issue at hand with comments about the weather won’t work.

We don’t need any October surprises in this already abnormal US presidential election (or a September one), and hopefully Ms Clinton really is as right as rain. Her schedule has of course been relentless and anyone might come over wobbly after standing in that heat and sun at the 9/11 remembrance service.

Clinton can’t afford another bout of protracted speculation about her medical well-being. The video already up on social media that seems to show her sagging into the arms of secret service agents as she tried to board a van to leave the 9/11 event will be played over and over and over.

In pictures: Hillary Clinton's 2016 presidential bid Show all 30 1 /30 In pictures: Hillary Clinton's 2016 presidential bid In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 11/09/2016: Hillary Clinton waves to the press as she leaves her daughter's apartment building after resting in New York. Clinton departed from a remembrance ceremony on the 15th anniversary of the 9/11 attacks after feeling "overheated," but was later doing "much better," her campaign said AFP/Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 25/08/2016: Hillary Clinton speaks at a campaign event in Reno, Nevada AFP In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 27/07/2016: US President Barack Obama and Democratic presidential nominee Hillary Clinton embrace on stage during Day 3 of the Democratic National Convention at the Wells Fargo Center in Philadelphia, Pennsylvania AFP/Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 11/07/2016: Bernie Sanders officially endorsed Hillary Clinton, saying his progressive vision for ‘a transformed America’ would be ’best served by the defeat of Donald Trump’ Reuters In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 26/06/2016: New York Governor Andrew Cuomo, former Secretary of State and Democratic Presidential candidate Hillary Clinton, Al Sharpton and New York mayor Bill de Blasio march during the New York City Pride March in New York City Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 7/06/2016: Democratic presidential candidate Hillary Clinton gestures as she greets supporters at a presidential primary election night rally in New York AP In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 26/05/2016: A supporter of democratic presidential candidate former Secretary of State Hillary Clinton holds up a shirt during a campaign event in San Francisco, California Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 26/04/2016: Hillary Clinton embraces her husband, former President Bill Clinton, at a primary night campaign event in Philadelphia, Pennsylvania. Early results indicated Clinton would win Pennsylvania's presidential primary Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 8/03/2016: Hillary Clinton and Bernie Sanders during of the CNN Democratic Presidential candidates' debate, at the Whiting Auditorium in Flint, Michigan EPA In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 3/03/2016: Singer Katy Perry raises arms with U.S. Democratic presidential candidate Hillary Clinton at the end of the Hillary Victory Fund "I'm With Her" benefit concert at Radio City Music Hall in the Manhattan borough of New York City REUTERS In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 28/02/2016: Hillary Clinton delivered a victory speech in Columbia AP In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 16/02/2016: Hillary Clinton speaks at a rally at Truckee Meadows Community College in Reno, Nevada AP In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 9/02/2016 (L-R) Priyadharshini Shanthakumar, Hattie Hughes and Claudia Blair with Hillary Clinton campaigning in Derry, New Hampshire Hattie Hughes In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 30/01/2016: Hillary Clinton is introduced by her daughter Chelsea while the two campaigned together at a 'Get Out The Vote" caucus' event at the Carrollton Inn in Carroll, Iowa Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 14/12/2015: Hillary Clinton speaks during the National Immigrant Integration Conference in New York City. During the speech Clinton announced her immigration proposals if elected president Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 9/11/2015: Hillary Clinton speaks on stage during a rally after filing paperwork for the New Hampshire primary at the State House in Concord, New Hampshire. Each candidate must file paperwork to be on the New Hampshire primary ballot, which will be held on 9 February 2016 Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 22/10/2015: Hillary Clinton avoided major damage to her presidential campaign during a nearly 11-hour congressional hearing dominated by Republican criticism of her response to the Benghazi attacks AFP In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 9/09/2015: Hillary Clinton takes part in a discussion after speaking about the Iran nuclear deal at the Brookings Institution in Washington. Clinton expressed firm support for the nuclear accord with Iran, calling it flawed but still strong. Clinton added that the agreement must be strictly enforced and said that if elected president next year, she would not hesitate to use military force if Iran fails to live up to its word and tries to develop a bomb AFP/Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 8/09/2015: Hillary Clinton does the "Nae Nae" dance move with DJ Stephen "Twitch" Boss (L) and television host Ellen DeGeneres (R) during a taping of "The Ellen DeGeneres show" in New York In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 26/08/2015: Hillary Clinton greets guests during a campaign event at Tabor Home Vineyards and Winery in Baldwin, Iowa. A recent poll has Clinton leading all other Democratic contenders in Iowa by about 30 percentage points Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 13/07/2015: Hillary Clinton poses for a selfie with a student outside the New School after speaking to outline economic vision in New York. Clinton promised to raise incomes of hardworking Americans and rein in excesses on Wall Street in the first major economic policy address of her 2016 campaign AFP/Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 15/06/2015: Hillary Clinton speaks during a forum on early childhood education at the YMCA of Strafford County in Rochester, New Hampshire. Clinton held a formal launch event in New York City, and is hitting the first in the nation primary state for the third time since announcing her candidacy in April Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 22/05/2015: Hillary Clinton tours the Smuttynose Brewery in Hampton, New Hampshire Getty Images In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 23/04/15: Hillary Clinton addresses the Women in the World Conference in New York City Getty In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 22/04/15: Hillary Clinton waves to college students as she leaves after speaking during the Hillary Rodham Clinton Award for Advancing Women in Peace and Security at Georgetown University in Washington AFP/Getty In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 21/04/15: Hillary Clinton meets with audience members after speaking with students and faculty of New Hampshire Technical Institute in Concord, New Hampshire. The conversation revolved around higher education, manufacturing and women in the work force Getty In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 13/04/15: “Loaded the van & set off for IA. Met a great family when we stopped this afternoon. Many more to come.” A picture of one family Hillary Clinton met on her road trip, which she tweeted In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 12/04/15: The building that will house Hillary Clinton's campaign headquarters, on the corner of Pierrepont and Clinton Streets in historic Brooklyn Heights, NY Corbis In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 12/04/15: Some expect Hillary Clinton’s campaign to cost more than Barack Obama’s $1bn in 2012 EPA In pictures: Hillary Clinton's 2016 presidential bid Clinton campaign 12/04/15: Hillary Clinton formally declares in a video that she will seek the Democratic Party’s presidential nomination for 2016, and says she wants to bring the benefits of the economic recovery to all Americans AP

It was her misfortune that it happened at an event the whole country was tuned into. Which of course, immediately makes you wonder. How many other episodes of this kind might she have suffered away from the eyes of the public?

And the Republicans will not hesitate one second to take advantage and encourage a new whispering campaign on whether or not she is up to the job of running the nation. Even before Sunday Donald Trump had been deliberately posing questions about his rival’s health and stamina, most recently when she was seen having a coughing fit while trying to talk to reporters on her plane.

“Mainstream media never covered Hillary’s massive ‘hacking’ or coughing attack, yet it is #1 trending,” Mr Trump tweeted Tuesday. “What’s up?”

The email affair is serious, of course, because it is about whether Clinton, who is 68, might have given the country’s enemies easy access to classified information, possibly jeopardising national security. But questions about a presidential candidate’s health are too.

It was problems with mental health that forced Thomas Eagleton to abandon his quest for the White House more than four decades ago. Paul Tsongas, a former US Senator, insisted he was clear of cancer when he ran for the Democratic nomination in 1992. He didn’t win, but the disease was to claim his life in January 1997.

By some accounts, Ronald Reagan, who was 70 at his inauguration, was afflicted with Alzheimer’s Disease long before he ended his second term in office.

A recent Rasmussen Poll said that almost 60 per cent of American voters think that presidential candidates should release their most recent medical records before the country goes to the polls. That is a much higher proportion than even four years ago and may reflect the anxiety that Clinton’s health has been stirring for some time.

Clinton, we know, suffered a concussion after fainting at the end of 2012, an event that was included in medical records that were released by her physician, Dr. Lisa Bardack, at the beginning of the campaign in July 2015. She said the former Secretary of State is “in excellent physical condition and fit to serve as President of the United States”.

Trump has hardly been a model of transparency when it comes to his medical fitness, so far releasing nothing more than a brief letter from his doctor saying he is in fine health all round. If he is going to continue to make an issue of Clinton’s physical fitness, he should be obliged to be more forthcoming too. (We will leave his refusal to release his tax returns for another day.)

But Clinton: if it really was merely the heat and fatigue getting to you on Sunday morning, then make sure you give us all the details you can before the conspiracy theorists get busy and convince the nation that you are in fact suffering from something much worse.