Usually the rantings of a vice president are considered largely irrelevant to the campaign. That was the narrative of “it’s just old Joe” when last time around he claimed that FDR spoke about the Depression as a supposed president in 1929 and on television no less, and other such crazy things. But recently Joe Biden recently has sounded utterly unhinged. In his contest with Paul Ryan, his gesticulating and snickering would have gotten him kicked out of a high-school debate. And on the campaign trail, he thinks there are American veterans of an Iran war, that when in Ohio he is in Iowa, and now that Romney would extend a 500 trillion-dollar tax cut to the wealthy (about 35 times larger than the U.S. GDP). In each one of these instances, one can attribute the weirdness of Biden to the exhaustion of the campaign trail and the swirl of travel, but after a while the examples are cumulative, and the tally unmatched by the other candidates. That Biden is a campaign liability was always unmistakable; that he is now still fit to be president grows more questionable every day.