Ever since Pravda, we News International slaves have had to be routinely rude about every new work by Sir David Hare, the celebrated theatrical knight and left-wing thinker, or face the sack. All right, this is a joke. Actually, we can say what the hell we like about Hare. Unfortunately, in this case, his new play “about Iraq”, a certain amount of rudeness really is called for.

Nadia Blye is a Yale academic specialising in international relations, formerly a war reporter, and a conviction-liberal who nevertheless supported the invasion (the “liberation”, as she crisply rephrases it). She and her boyfriend, Philip, are over in Shropshire visiting Philip’s raffish father, Oliver, a bookish doctor, serial philanderer and sardonic opponent of the whole Saddam-toppling business.

The setup sounds interesting, and Hare at least makes a stab at giving Nadia some vaguely arresting lines. He doesn’t allow us anything really meaty, such as reminders of Saddam’s atrocities against the Kurds, his virtual extermination of the Marsh Arabs or his $25,000-a-pop sponsorship deal for the families of Palestinian suicide-bombers. But Nadia is at least an ardent and likeable character. The trouble is, you know with a weary inevitability that sooner or later she is going to proved Wrong and Oliver Right.

When it finally comes, however, the moment is so crude in its manipulativeness as to beggar belief. Can this really be one of our most prominent playwrights at work? All Oliver has to do is dose Nadia with chardonnay, deliver a quick monologue about the limitless violence and wickedness of the Great Satan (apparently, the Bush administration’s working principle was, “It doesn’t matter if tens of thousands of people get killed, just so long as they’re not Americans”), and she promptly crumples, weepily acknowledging “No, you’re right” and lamenting – “Jesus, what a mess”.

The opening scene is also insultingly sermonical. Nadia is in a tutorial with a student who is patriotically American, regards capitalism as the natural order of things, believes in the rule of law and private property rights, and, just in case we were still wondering, is shown to be REALLY THICK. At times like this, you wonder: why bother having actors on stage at all? Why not just have the playwright striding about on stage, waggling finger puppets at us and doing all the voices himself? Or, easier still, delivering a stern, schoolmasterly lecture?

It is not so much about where you yourself stand on the rights and wrongs of consumer capitalism or the never-ending war against terror. It is about theatre, which ought to surprise and challenge. Yet every time English theatre swivels its little head to look at America, Iraq, Bush or any allied subject, you know what is coming. You begin to long for a rabidly neocon but passionate, witty, satirical play laying into left-liberal pieties and cheese-eating surrender monkeys everywhere. At least it would be original.

Other elements are similarly tired and unimpressive. The personal is political, apparently. Yale students find that the war in Iraq makes them despair of the world to the point of impotent cynicism, if not outright nihilism. This utterly fails to convince. Most people’s daily lives and relationships in the West are, for better or worse, almost entirely unaffected by the war in Iraq. Its only tangible effect, perhaps, has been to make us all a little more wary about grandiose foreign ventures and simplistic political promises of setting the world to rights.

There are some compensations in Jeremy Herrin’s production. Indira Varma is excellent as Nadia, with her fine-featured intelligence. Even her nose looks intimidatingly clever, and she captures American body language with great skill, all wide open gestures of confidence and candour. Anton Lesser is equally good as Oliver, with his expert, needling flirtatiousness and sudden little grin. And Mike Britton’s set beautifully suggests the English summer garden where all these long, rambling pseudo-debates take place, with yellowy summer light (by Howard Harrison) and a canopy of branches high overhead.

Aside from the otiose Iraq stuff, the verbal sparring between Nadia and Oliver is often entertaining, as are the sharp observations on relationships and the eternal choice between peace and passion. The second half sags badly, though, pacing is slow, then we get that appallingly neat moment of Nadia’s “revelation”. The final impression you are left with is of laboured, join-the-dots preachiness and great waffly chunks of dialogue that go nowhere in particular. This is oppressively argumentative theatre, short on a sense of healthy chaos and humour, and almost entirely lacking in imagination.

Royal Court, SW1

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