The weather in Washington has changed. Along with the cold snap has come the most serious storm of George W. Bush?s presidency. Everywhere you go the conversation is about authority draining from the White House. On Capitol Hill, the Republicans? legendary discipline has fractured. Mr Bush?s public approval rating is marooned below 40 per cent. Everyone is talking about bringing the troops home from Iraq.

The image that will forever haunt this president is of the mission accomplished banner that served as backdrop to his triumphal landing on the aircraft carrier USS Abraham Lincoln in those heady days of May 2003. Now, cynics will tell you the banner will soon be dusted down and unfurled again ? only this time the purpose will be to give political cover to an American retreat from Baghdad.