Balkinization has a discussion on why it is that the 25th amendment provides a way to dispose of an incompetent President, but there doesn’t exist a similar way to dispose of an incompetent Vice President.
Since Americans are determined to think that our Constitution is basically perfect, I cannot help but wonder what we would do if something did indeed happen to Bush and Cheney became President for, say, the last 550 days of their term. (For that matter, he might announce his desire to run for the presidency in his own right, now that he occupies the Oval Office. Who knows?) Would we (correctly) view this as driving over the cliff and, at long last, having to confront the adequacy of the Constitution? Or, as with the electoral college and 2000, would we simply follow Bobby McFerrin’s advice “don’t worry, be happy”?