The unexpected death of Supreme Court justice Antonin Scalia has set up a showdown between President Barack Obama, who says he will nominate someone to Scalia's now vacant seat, and Republicans in the U.S. Senate, who say it should be the next president who makes the selection. WGBH All Things Considered host Barbara Howard spoke with Harvard University law professor Noah Feldman about what's to come in the wake of Scalia's death.