Senate Republicans refusing to countenance filling the US supreme court vacancy have, so far, been able to make it a debate about abstract concepts. But when Barack Obama names his nominee, that is set to change. “They just keep digging themselves in a deeper and deeper hole,†Democratic senator Chuck Schumer said on Tuesday. “If anything, when the president nominates someone and there’s a real live person there, and I’m sure that person will be a very reasonable person to be on the court in the American people’s eyes, it’s going to get worse for them. It’s not going...