As she prepares for the second presidential debate this Sunday, Hillary Clinton's advisors have a hard question to answer - nothing to do with policy or probity. A picture is worth a thousand words, and the problem is this: how to dress for the big day?
One of her signature pantsuits in a bold block colour? Or is that too same-y? A different block colour, maybe? The fact is there aren't that many models for how a 69-year-old woman should look, assuming she needs to go authoritative, rather than a cardiganed cosy. This is one way Trump does have it easy.
No-one of course has been here before, at least not in America. No-one has had to contemplate how to dress a female future President, even if Michelle Obama, and Jackie Kennedy before her, have totally cracked First Lady. So what could Clinton's advisors learn from countries with a longer history of power dressing? Or come to that, just plain from history?
Three exhibitions in the UK at the moment focus on the wardrobe of Queen Elizabeth II, with its style of traditional but un-fluffy femininity. But her look wouldn't necessarily work for Hillary. There's no man trying to take the Queen's position away. Team Clinton are anxious - as one supporter put it - not to rub voters' faces in the fact that she's a woman. Hence those trouser suits - and if they do wind up looking a bit like a uniform, that's no bad thing, maybe. (Even Queen Elizabeth II dons military uniform for certain ceremonies, and relishes every brass button, they say.)
There are lessons to be learnt from an earlier queen, and one who really did have to run her
country. (Had to fight to win it, too, as surely as any candidate today.) Elizabeth I knew all about the power of clothes. In her early days as a Protestant princess she made a point of dressing with a modest plainness, to make a contrast with her Catholic sister Mary. Later, the glory of her wardrobe would be legendary. One dress was embroidered with eyes and ears, to signify that Elizabeth saw and heard everything in her country.
Mary Queen of Scots - another female ruler - was another who used clothes as symbols. On the morning of her execution, spectators gasped as she threw off her black dress to reveal a petticoat of tawny red - the colour of dried blood, and of Catholic martyrdom. It may be a tad less dramatic, but Hillary Clinton's charm bracelet, containing a picture of her granddaughter, conveys a message just as clearly: 'I'm a warm family woman. Honestly!' When Angela Merkel debated with a rival before her last election, her necklace, in the colours of the German flag, got better reviews than any of the speeches. And that's even before we've got on to Theresa May.
You can't pick up a paper at the moment without seeing something about a powerful woman's clothes. The V&A museum will put some of Margaret Thatcher's outfits on display - more suits, though not pantsuits this time. More block colours: well, they do work for the camera, not something that Elizabeth I had to worry about. Theresa May, of course uses strong colour and simple shapes. The red, white and blue of the Union Jack to meet Scotland's Nicola Sturgeon - who also wore the colours of her country. A navy and lemon yellow coat to meet the Queen, with a statement necklace and her trademark leopard shoes.
There's been much talk in the press of May's taste for kitten heels - and much talk about the talk, when we'd never discuss a male politician's footwear in the same way. But that perhaps is to miss the point - those shoes are a sop May can throw to the press, effectively. Public opinion can pick away at those kitten heels - whether they speak femaleness, or folly; whether true liberation lies in dressing without fuss, or in dressing to your own fantasy.
May's shoes keep snipers away from any more serious area of vulnerability. And as Prime Minister of Great Britain May, is daring to dress - like Michelle Obama, like both Queen Elizabeths, actually - in a way that adds to, rather than apologises for, her femininity. Hillary Clinton's advisors, take note. Because in these fraught times a female politician needs every weapon she can lay hands on - just as she did in the sixteenth century.
Sarah Gristwood is the author of Game of Queens: The Women Who Made Sixteenth-Century Europe, published by Oneworld on October 6.