There’s one thing Donald Trump knows how to do well: maximizing suspense in an elimination contest and treating contestants with exquisite cruelty. Competing for a spot on his presidential ticket is as close as politics can get to The Apprentice, the show that fooled millions of Americans into thinking that Trump was a successful businessman. A number of Republican candidates for running mate, from the endlessly self-humiliating Tim Scott to the nondescript Doug Burgum, are vying for what surely looks like a political suicide mission: they must know that Trump betrays everyone eventually, yet they seem to think that their...