In the best of all possible worlds, President George W. Bush would nominate a person of ability, integrity and independence to replace Alberto Gonzales, the political lackey who last week resigned as US attorney-general.

There is little chance he will find such a person: good candidates will not take the job and bad ones will not make it through the partisan Senate confirmation process. It is hard to see how the US can end up with the attorney-general it needs – one who can say no to the imperial presidency and impose real limits on executive power in the treatment of detainees and beyond – anytime before the next presidential election.