Bolton's possible future colleagues at the United Nations say he is not one to think of himself as bruised by a Washington political battle, but the U.N.'s member states are all watching the confirmation process, and some diplomats believe he'll be damaged goods upon arrival. But once he's at the United Nations, it's not obvious that anybody will treat him differently over the long run because of the confirmation delay. Holbrooke's confirmation was delayed over a year, and he largely shrugged it off, though his delays were caused by less personal objections.
What if the Senate doesn't confirm Bolton today?
Administration officials privately concede that Bolton may not make it. Bush could appoint Bolton to the job while the Senate is in recess, but that is almost universally viewed as a bad idea -- member states would almost certainly question his authority, at least initially, and the Senate would probably never confirm him for any future job.