A Royal Welcome, Royal Court, London

In an interview last week, George Bush revealed that he has been to London once before. He knows that because he remembers seeing Cats. It's doubtful that he has even heard of the Royal Court, and would probably think that John Osborne is some distant relative of Ozzy. But that did not stop England's national theatre of new writing from giving him A Royal Welcome at lunchtime on Wednesday. His wife Laura even managed to slip away from her official engagements to appear on stage at the Sloane Square theatre before a packed and appreciative house.

The first lady of the USA materialised in the shape of that veteran of the Workers' Revolutionary Party and sterling campaigner for Palestinian rights, Vanessa Redgrave - an incongruity that caused a delighted yelp of laughter from the audience. But in a spellbinding performance - all the more remarkable for having had one morning's rehearsal and being read from a script - Redgrave turned that knee-jerk mirth into something altogether more thoughtful.

Entitled Only We Who Guard the Mystery Shall Be Unhappy, the piece itself was a coup for the occasion - the world premiere of the first scene of the latest epic-in-progress by Tony Angels in America Kushner, who, last year, in Homebody/Kabul, took a profound and prescient look at the clash of values between East and West. It imagines Laura Bush on a school visit to help with the reading programme. Exuding genuine motherliness and shy warmth, she remarks that while the children look "real sweet in their PJs", she is puzzled by their attire. "Perhaps this is the first time you have read to dead children," responds the angel/teacher.

This fantastical encounter between the first lady and the spectral infant victims of US sanctions and non-precision bombing could have been the occasion for some easy point-scoring in questionable taste. In Kushner's hands, though, it becomes a haunting episode, flecked with hilarity: an official visit on which a dreamy, gentle-spirited wife finds herself no longer able to sustain the official line on her husband's foreign policy. "Bushy", she reports, with a virtuoso imitation of his snoring, sleeps soundly while she devours books in bed. "Well, he's tired a lot - from the gym."

Her preferred reading is Dostoevsky, and she proceeds to give the children (who can speak to her only in birdsong) a gripping description of the story in The Brothers Karamazov, in which the Grand Inquisitor arrests Jesus when he comes back to earth during the Spanish Inquisition. Do people want freedom (the vertiginous choice offered by Christ) or freedom from freedom (provided by the enslaving institution of the Church)? Under the gaze of the murdered children, it becomes painfully clear which side of the argument Kushner's Laura feels that she has until then endorsed.

This tantalising preview of a lengthy drama was flanked by two sketches. A verbatim collage of the exchanges in a website chatroom, Caryl Churchill's Iraq.Com demonstrates how reason fights a losing battle amid the shockingly abusive e-mails sent between Iraqis and Americans. Martin Crimp's Advice to Iraqi Women takes the ironic, straight-faced Swiftian approach of offering earnest tips on how to keep children safe, as though it were lecturing cosseted middle-class Westerners.

"If you have a mud-scraper outside your door, bind it with a cloth... Test for food allergies every three days." In this context, images derived from warfare - "A home is a potential war zone... your house is a minefield..." - sound like the grotesque exaggerations of people who don't even know that they are alive.

A pity that the Bushes didn't show, except fictionally, but it was a right royal, and very stimulating, welcome.