Why? Because before he got elected, Donald the Reasonable would have to take a position on abortion. He would undoubtedly try to find some kind of nuanced lane, to use the au courant word, somewhere in between the standard Democratic and Republican positions. But this of course would just dissatisfy both parties. And as the Republicans appear to be moving toward a position that doesn’t even acknowledge the traditional three exceptions, any deviation from that by D the R will brand him just another baby killer.

He will have to take lots of positions, this fellow. On same-sex marriage. On whether insurers should be compelled to cover contraceptive services. On immigration and citizenship. On who his model Supreme Court justices are. On free trade. On a minimum wage. On how much he’s willing to mix it up with Putin. On whether Hollywood and the universities are ruining America. On climate change. He can’t run for president saying, “Well, sure, all those things are important, but what I’m really all about here is implementing the ideas of Raj Chetty.”

In other words, partisan choices are utterly inescapable.