MITT ROMNEY HAS BEEN running for president as the Republican nominee, de facto or de jure, for eight months now, and the grand historical joke of it has not yet worn off. A party that has set itself to frantically, fanatically expunge its moderates, quasi-moderates, suspected moderates, and fellow travelers of moderates chose as its standard bearer the lineal heir, biographically and genealogically, to its moderate tradition. It entrusted its holy crusade to repeal Barack Obama’s hated health-care law to the man who had inspired it and run, four years before, promising to do the same for the rest of America. The man and his historical moment could not be more incongruous. It was as if the Mongol tribes of the thirteenth century, setting out to pillage their way across the Asian steppe, had somehow chosen Mahatma Gandhi as their supreme khan.