Two of the three guys in the prime risk category who want to be President of the United States next year debated in a largely empty studio Sunday night. Both Joe Biden and Bernie Sanders proved themselves to be preferable alternatives to the angry talking yam presently in the White House. In that sense, they were both “presidential,” if that word means anything any more. Biden kept trying to pivot to the current emergency, and largely was successful in doing so, especially in his close. On the other hand, Sanders, who seems to be on his way to another severe nationwide hiding this Tuesday, kept trying to pin Biden on his past record on issues like Social Security and (especially) the calamitous war in Iraq. Absent the cheering crowds, these points seemed sharper and more interesting.