When Donald Rumsfeld,US defence secretary, twice offered to resign amid the Abu Ghraib torture scandal, President George W. Bush refused. When Tom DeLay, the House Republican leader, was under a cloud for allegedly taking trips paid for by super-lobbyist Jack Abramoff, Mr Bush invited him aboard Air Force One.

So it has been strange this week to watch Mr Bush avoid even the slightest expression of public support for Karl Rove, his political right hand and the man most responsible for the president being president.