President George W. Bush has always had an imperial vision of the US presidency. Losing control of Congress has, if anything, made him more determined to wield the weapon of unfettered executive power whenever he can get away with it.

The past few weeks have been one long power play by Mr Bush: on everything from the Iraq war to the firing of federal prosecutors and the wiretapping of American telephones, the White House has been both aggressive and defiant. Last week, the combative president even tried to launch a stealth takeover of the US regulatory system, putting a White House commissar into regulatory bodies such as the Environmental Protection Agency – and increasing the risk that such expert agencies will set policy by the dictates of politics rather than science.