Hilary Mantel on Margaret Thatcher: 'I can still feel that boiling detestation'

Hilary Mantel on why it took 30 years to finish her Margaret Thatcher story

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Hilary Mantel
Thatcher was 'the very stuff of drama' … Hilary Mantel. Photograph: Sarah Lee for the Guardian

Hilary Mantel has had Margaret Thatcher in her sights for more than 30 years. Somewhat surreally, the prime minister wandered into view around noon on Saturday 6 August 1983. Mantel's flat, on a quiet Windsor street lined with cherry trees, overlooked the private hospital where Thatcher was having an eye operation. She was just standing by the big sash window in her bedroom when she spotted Mrs Thatcher "toddling" around the hospital gardens unguarded.

"Immediately your eye measures the distance," says Mantel, measuring each syllable, her finger and thumb forming a gun. "I thought, if I wasn't me, if I was someone else, she'd be dead."

Imagining you are someone else is the essence of fiction. Mantel has been a medium, in Beyond Black, a giant, in The Giant, O'Brien, and most successfully, Thomas Cromwell in Wolf Hall and Bring Up the Bodies. Both won her the Man Booker prize and are now packing theatres in London and soon, perhaps, Broadway. "We're in negotiations now," says Mantel, in a tone that you wouldn't try to negotiate with. The television adaptations, starring Damian Lewis as Henry and Mark Rylance as Cromwell, have just finished filming. She's part-way through The Mirror and the Light, the last in the trilogy: "I don't write chronologically so I can't say where I am exactly but it's not finished. It should be done next year."

Her dark new short-story collection offers her a break from the Tudors. The stories range from the subtly sinister to the outrageously gothic. "I was going to call it 'Ten Transgressive Tales'," she says. "But then, after 30-some years, I finally finished my Thatcher story."

In "The Assassination of Margaret Thatcher", Mantel succeeds where terrorists failed. It's an unexpectedly funny exploration of the Maggie mythos, delivered with sniper-like skill. It's a horror story for Thatcher's fans, a wish-fulfillment fantasy for her detractors. Either way, it's shocking.

So, why has it taken Mantel so long to pull the trigger on this tale? "I just couldn't see how to get [the characters] to work together. They must examine their own myths and those of their communities. Each colludes for their own reasons."

Was she freed by Thatcher's death? "I am concerned with respect. I'm not concerned with taste. I would have happily concluded the story in her lifetime but couldn't – it was my technical difficulty, not any delicacy. I believe in walking that line. You mustn't be too timid to risk getting it wrong."

Last year, Mantel was thrown in the stocks for describing the Duchess of Cambridge as a "plastic princess born to breed" in a lecture on "Royal Bodies". She is uncowed at the prospect of more "fuss"."As a writer you have a choice to make – are you going to accept censorship or not? In the case of the duchess, the great outraged weren't at the lecture and didn't read the article. I was saying: 'Please back off and treat this young woman as human.' I was speaking in her favour. I wouldn't be so petty as to criticise someone for their appearance. Look at me and Mary Beard and all the other women whose arguments are not engaged with or are dismissed because of fixations with appearance."

Thatcher was "the very stuff of drama," says Mantel. "She is a fantastic character. Why did she – does she – arouse such strong reactions?"

"When I think of her, I can still feel that boiling detestation. She did long-standing damage in many areas of national life, but I am not either of those people in that room [the characters in the story]. I am standing by the window with my notebook." And yet, the trigger is pulled.

"I never voted for her, but I can stand back and appreciate her as a phenomenon. As a citizen I suffered from her, but as a writer I benefited."

Charisma, power and persuasiveness are key qualities of Mantel's main obsession: Thomas Cromwell. Was Thatcher a Cromwellian figure?

"Creativity in politics is rare but I think she had it," Mantel admits. "Cromwell did too. But he was a negotiator and she detested consensus – she saw herself as an Old Testament prophet delivering the truth from on high. Cromwell used history to pretend the new things he was doing were old, and thus to soothe the English temperament. Mrs Thatcher despised history as a constraint."

Mantel, like Cromwell and Thatcher, is self-made – her mother was a mill worker and her father left when she was 11. But, Mantel believes, Thatcher hated the end result of her self-transformation: "She couldn't turn herself into a posh girl with the right vowels. If you're that dissatisfied with yourself you try to fix other people, and if they won't be fixed you become punitive.

"It's true that no one can now say a woman can't run the country, but I think she set back the cause of women in public life. She imitated masculine qualities to the extent that she had to get herself a good war. The Falklands was great stuff – limited casualties, little impact on the home front and great visual propaganda. I am not suggesting this was conscious. I suspect Thatcher was the last person in the world to be able to examine her inner life, but she could sell a myth. The idea that women must imitate men to succeed is anti-feminist. She was not of woman born. She was a psychological transvestite."

Damian Barr is the author of Maggie and Me, published by Bloomsbury. The Assassination of Margaret Thatcher is published by 4th Estate (£14.99) on 30 September. To order a copy for £11.99 with free UK p&p call Guardian book service on 0330 333 6846 or go to guardianbookshop.co.uk.