Is this a PM we see before us?

Who'd have ever thought it? Norman Fowler, bespectacled Secretary of State for Health and Social Security in Margaret Thatcher's government, is a telling bit player in a new play at Hampstead Theatre, Jonathan Harvey's gay chronicle, Canary, and the man who proposes handy hints for homosexuals planning to, well, have sex together, in the incipient AIDS-age of a brave new political dawn.

He and Maggie are mulling over the finer points in a draft document. "I don't like anal sex," says the absolute Prime Minister, wielding her true-blue pencil in a smart vignette by the brilliant sitcom actress Paula Wilcox, clutching a handbag and challenging memories of other Maggies embodied onstage and screen by Angela Thorne, Lindsay Duncan and Sylvia Syms, to name but three of the best.

Mrs Thatcher has become an ambiguous theatrical institution over the years: a flash point for the pompous war against Argentina, a signal supporter of "good works" in the community, a pantomime dame and wicked fairy, and a prominent supporter of the West End musical Evita, whose oratorical aria became her own special anthem. But are we in danger of allowing such wicked impersonations to replace the real thing?

The current Chichester Festival production of Yes, Prime Minister, a new farce with a serious, but not at all dated message, has reactivated the comedy of tension between an elected political leader who knows nothing and his wily old senior civil servant who knows everything. But even this take on our political system has been eclipsed by the almost unbelievable drama of the recent general election.

Lopsided representations of our political leaders have always been a common feature on stage. Mrs Thatcher has always been portrayed as a dangerous werewolf, never a feminist, ideological innovator: she remains, in the theatre, a demonized hate-figure, with metaphorical scary tattoos. Norman Fowler in Canary is played by the actor as a regressive nerd. Even I know that Fowler wasn't – isn't? – exactly like that. Does this matter? Do we expect our parliamentary representatives to match our low opinion of them when we portray them on stage? And why should we expect them to measure up to their fictional representatives?

The actress, fashion designer and dedicated party-goer Sadie Frost recently admitted that meeting Gordon Brown "in the flesh" on the hustings during the election campaign was almost unbearably exciting: as if, like the rest of us, she'd been immunised against the reality of Brown's existence by the constant image of him filtered through our everyday media, not least through the groundbreaking television debates.

As well as Fowler in Canary, we have the similarly unexpected novelty of Mrs Mary Whitehouse, played by a big but not too butch male actor, Philip Voss, asking the audience to help shine a light into the murky corners of same-sex promiscuity.

Mrs Whitehouse, who ran a righteous "clean up TV" campaign against the BBC for decades, and organised the 1971 Festival of Light to which Harvey's play openly alludes, was a bit more than a bit player: in 1982 she brought an unsuccessful private prosecution against Michael Bogdanov, director of Howard Brenton's The Romans in Britain at the National Theatre, on the curious grounds of his "procuring an act of gross indecency", as though theatre and real life were the same thing.

All the same, Whitehouse could be said to have embodied a serious spirit of enlightened feminism, though it was never perceived as such at the time (nor is it in Harvey's new play), and a feminist theatrical undertow in British politics has been a powerful fact of theatrical life ever since Ibsen and Shaw created the "new woman" in their plays at the end of the 19th century. That new woman has been cropping up lately in all sorts of shapes and sizes, majoring in health care for refugees from the Middle East and minor-ing in self-care back home.

And in the new political feminist dramas of No Expense Spared at the Jermyn Street Theatre this month, and in the Women, Power and Politics season at the Tricycle in Kilburn in July, she suddenly emerges as an all-round political life force: parliamentary candidate, virgin queen and rebel.

Playwright Richard Stirling, a biographer of Julie Andrews and author of No Expense Spared, says that writing about politics creates a useful bulwark against the endless bickering, and that actress Joanna McCallum in his play embodies a lively mixture of Baroness Trumpington and Bessie Boothroyd, the House of Commons speaker with a showbusiness background.

The best line in this ongoing, interconnected satirical meltdown in our public life is on Private Eye's new cover this week: the Queen touched up for a six-figure sum by her former daughter-in-law in exchange for a meeting with her own second son. (Which reminds me, in turn, of the anecdotal riposte of a swish Manhattan theatre-goer recounted by Jonathan Miller, who, when approached by a beggar in Times Square for the price of a cup of coffee, said: "Coffee, coffee, look what it's doing to you!")

Still, the television debates during the election campaign and their spin-offs, the subsequent Q and A's, have created genuine new interest in social and economic issues. All at once, political rhetoric is again seductive, oratory almost de rigeur in our daily conversations. What do we think, therefore, of the new on-stage presentations of Alastair Campbell and Tony Blair, who are both suddenly available for all sorts of chat shows and debates, if the money's right? This is part of the commercialisation of politics that leaves the general public dismayed and disbelieving.

Which is why politics has been renewing itself, God bless it, in the theatre. Where else would you get excited about the miners' strike of the mid 1980s except at the long-running musical of Billy Elliot at the Victoria Palace, with its still surprising agitprop interlude, or at Jonathan Harvey's Canary at Hampstead Theatre? And how would you renew your interest in the suffragette movement and the history of the Labour Party without discovering, at the little Finborough Theatre near Earls Court, an upcoming revival of J M Barrie's What Every Woman Knows, a play not seen in London since Maggie Smith starred in it 50 years ago?

The recent sell-out success of Laura Wade's Posh at the Royal Court has proved once more that politically provocative theatre, when it's well-written and well-acted, is still the best sort of theatre in the world. And the play contained a metaphorical character study – or at least, implied social analysis – of the new Prime Minister, David Cameron, represented by a member of the Bullingdon Club whose yobbish but sacrifical bad behaviour by association (he owned up and "took one for the club") is smoothed over by the party machine "fixer" who has spotted a winner in the ranks. In the same way, Barrie's play, in 1908, was a loose but significant re-telling of the early career of the Labour Prime Minister, Ramsay Macdonald.

There are a couple of plays by George Bernard Shaw that show politicians in action and not at all to their advantage. They have not dated. In The Apple Cart, a rum bunch of intellectually challenged ministers discuss the future of democracy with hilarious disregard to its true meaning, while a witty, unelected monarch propounds the virtues of a benevolent autocracy.

And in the Women, Power and Politics season at the Tricycle in Kilburn next month, we have the re-enactment of Margaret Beckett's campaign (supported by Clare Short) to lead the Labour Party in the wake of John Smith's sudden death, a period of British politics that led to the birth of New Labour but could have led, perhaps, to a better place; this debate will be taken up, surely, during Diane Abbott's campaign for the party leadership, and may well be kick-started in the north London theatre.

The playwright and satirist Alistair Beaton, once a speechwriter for Gordon Brown, believes that the fencing off of political power in the executive areas of the last government created a vacuum in our politics. There was not much actual debate in parliament, so theatre and television moved in on such vast subjects as Afghanistan and climate change.

You could easily argue that the only subtle public discussion of the genesis of the war in Iraq was held in David Hare's Stuff Happens at the National Theatre in 2004. That play created characters of political leaders that were, in some ways, more interesting than the leaders themselves. President Bush was shown to be a man of genuine principle, his Secretary of State Colin Powell to be someone of real intellectual flair in his consideration of the threat posed by Saddam Hussein; and Tony Blair was portrayed as a decently motivated operator in the top-table discussions.

The politicians themselves, of course, don't see it like this. At a recent Writers Guild conference, the former health minister and Paymaster General in Blair's government, Tessa Jowell, accused Alistair Beaton and his ilk of contributing, unhelpfully, to the popular cynicism about politicians, as if somehow the public were otherwise incapable of coming to some sort of critical conclusion about their elected representatives. Whether Tessa Jowell likes it or not, it seems our theatre remains an increasingly significant court of public appeal in our political and personal conduct.

For further reading:

'Strategies of Political Theatre: Post-War British Playwrights' by Michael Patterson (Cambridge University Press)