Andrew Sullivan raises a very good question
about the White House's likely need to find a new Attorney General. A logical person to replace Gonzales might be Deputy AG McNulty. But he's as implicated as his boss. So he's out. So is Bush loyalist Harriet Miers. So she's out too. In fact, most of the Bush insiders who are legal types are implicated. And even setting aside particular people, the senate would probably look very askance on another Bush pal as AG.
The political logic of the situation (ethical logic too, but we're far past that point, aren't we?) strongly suggests that the White House should tap a broadly respected lawyer public figure who can reestablish trust in the Department.
But can the president afford to have someone like that at the Justice Department right now? With all the investigations and potential investigations in play? A straight-shooter who will have justice's back rather than the White House?
This might be the only factor weighing in favor of Gonzales holding on to his job.