Princess Diana had a good heart, but spare us this cult of empathy | Christina Patterson

Watching the ITV film Diana, Our Mother, on Tuesday night, it was like falling in love again. Yes, of course she was beautiful. She had the smile of a film star. But it wasn’t just her beauty or the radiance that shone out of every frame. It was the compassion in Diana’s smile, and the kindness in her eyes that made a nation fall in love.

“People often asked me if I was in love with her,” said her friend Harry Herbert in the film. “I said of course I was. Everyone was.” And we were. It’s why cars and bikes chased her, and photographers spat on her, to get a reaction. It’s why her sons couldn’t have even one meal with her, on a mountain, without their mother having to beg the throng of paps to step back. And it’s why her brother’s electrifying eulogy at Westminster Abbey, which he discussed on BBC Radio 4’s Today programme this morning, triggered unprecedented applause.

Yes, it was partial. The film her sons agreed to was meant as a memorial to the mother they loved and lost. In memorials, we don’t mention the tantrums, the misery or the moods. But even if these had been included, they wouldn’t cloud a bigger truth about Diana’s very real ability to connect.

“I was thinking to myself,” said Harry in the film, “how is it so many people who have never met this woman, my mother, can be crying and showing more emotion than I am?” In the 20 years since, sociologists and cultural critics have tried to answer that question, but the answer is clear. “I think her humanity spoke to their humanity,” said Victor Adebowale, who saw a lot of the work Diana did with homeless people. We are all crying out for humanity. We pine for people who will make us feel that our hopes and dreams and fears have been heard. We long for people who understand our pain.

This is one of the reasons the prime minister dropped from a 20-point poll lead to something that looked very like defeat. She is, by all accounts, a decent woman. Constituents have said that they have seen her wipe away a tear when they have told her about private grief. But in public, she can’t do it. The term “Maybot” caught on because in public, at least, it’s true.

And it’s one of the main reasons Jeremy Corbyn went from rock bottom in the polls to a defeat that almost looked like a triumph. Sure, the promises to students helped. But it was more than that: people who see and meet him like him. They see that he cares about people who don’t have much. He listens to people and looks them in the eye.

We want our leaders to have good hearts. We want them to be human. We want to feel that our future is in the hands of people who understand our needs. In Jonathan Teplitzky’s recent film Churchill, Winston Churchill is very human indeed. He yells at his secretary. He drinks too much. He eats too much. He’s pompous. He’s self-pitying. He’s proud. His wife, Clementine, tells him that she’s sick of having to “live around” his “edges”. When he lies on his bed in a black cloud of depression, you can almost feel her longing to be set free from the gloom. But he’s gloomy because he’s worried. He knows that thousands of young men are about to lose their lives in the D-day landings. He has seen the price of war and he wants to be sure that these men will not die in vain.

Empathy and compassion are lovely. I’m glad that the man who will be king had a mother who taught him that these are good qualities to have, in a monarch or a man. It would be nice to have these qualities in a prime minister too, but this is not a time for nice. I want someone who understands that actions have consequences, and that when you get a policy wrong – in defence, fire regulations or the running of a health service – real people die. I want someone who understands that politics is not a game.

We don’t need to fall in love with a prime minister. We don’t need a king or queen of hearts. As we face Brexit, our biggest challenge since the second world war, what we need is competence and a cool head. What we need, in fact, is what we can’t seem to find: a leader who’s up to the task. Perhaps because it’s a pretty much impossible job.