Washington is searching for a successor regime to Saddam Hussein. It is an exercise in political science. Can an even passably democratic government be devised to take the place of a dictator who has stripped his people of decency and trust in others? Iraqis of all sorts are putting themselves forward: dissidents and exiles, former army officers who fled from Saddam in fear of their lives, men of substance certainly. But how representative are they? Why should Iraqis have confidence in self-selected and evidently ambitious leaders whose legitimacy is questionable? This is where the Hashemite family comes in. The last...