There's a very fundamental point about the recent U.S. Attorney scandal that I don't see being made, or at least I don't see it being made with enough force.
U.S. Attorneys serve, like Cabinet officers and any other appointed position, at the pleasure of the President.
But—and this point seems to escape the attention of many—the President is not a king, and we are not his subjects. The President is elected, he is the servant of the people, and he is always accountable to the people for everything. The President cannot act arbitrarily. We have both a right and a duty to demand an explanation for everything the President does, and the President has an obligation to provide a sincere and honest explanation for all his actions.
Bush did not act illegally in firing the U.S. Attorneys. But legality is only one constraint on the official actions of the President, and it's the lesser constraint. We have a right to demand political accountability, and evaluate the political acceptability of the President's explanation.
Since "malfeasance" didn't make it into the Constitution as a justification for impeachment, the firing of the U.S. Attorneys per se is probably not an impeachable offense. I don't know whether or not it was a good idea to leave malfeasance out; I can see benefits and drawbacks to both sides. However, we do have the power to demand an honest and sincere explanation, and Congress has the legal power to compel a truthful explanation.
I want to see Gonzales testify under oath to Congress and say outright, "We fired the the U.S. Attorneys because they wouldn't prosecute Democratic politicians for partisan gain, and because we wanted to shield Republican politicians from criminal investigation." (Fox News crawler: "President and AG acted legally in firing U.S. Attorneys.") And if he says anything but that, I want to see his ass impeached and in prison for lying to Congress—a felony. And then I want to see Bush's ass impeached for ordering Gonzales to commit a felony.