The single biggest reason Mitt Romney won't be president

Especially in 2016—when the Internet gives voters instant access to a record of flip-flops that, in pure numbers and severity, suggest that Romney is not merely a politician who has “evolved” or “matured.” He either abandons his convictions when political opportunity strikes—or he has none.

A short list of issues on which Romney has been both for and against: the minimum wage, stem-cell research, immigration reform, Social Security reform, campaign spending limits, an assault-weapons ban, bailing out banks and Detroit, capital-gains tax breaks, carbon limits to ease climate change, and a woman’s right to choose abortion.

And, of course, Romney inspired Obamacare before he ran against it.