A flurry of articles this morning have picked up on Sarah Palin’s very excitable Facebook declaration that she was coming to London meet “one of my political heroines, the “Iron Lady,” Margaret Thatcher.” The Guardian is predictably sneering. The Mail on Sunday had the scoop first and raised the question of whether Cameron would meet the former Vice-Presidential nominee and potential Presidential candidate of the American sister party.

In Downing Street you can imagine the battle lines being drawn already. This is the stuff that Steve Hilton’s nightmares are made of, yet Palin has an obvious glitzy appeal to the right of the party and tabloid media, something Andy Coulson will know instinctively. As PM it would be extremely discourteous for Dave not to meet and be photographed with Palin if she was in town, a coutesy British PMs have extended to lesser known American politicians. Guido’s transatlantic sources indicate that she could be over on this side of the pond in the Autumn, perhaps around the time of Conservative Party conference, just when Dan Hannan and Douglas Carswell will be launching their Direct Democracy version of the American Tea Party movement.

Another headache for the Cameroons will be what the Deputy Prime Minister has to say about all this, since Clegg was perhaps expecting to be invited to be the surprise speaker in Birmingham…