A radio interviewer asked me the other day if I thought bigotry was the only reason why someone might oppose the Islamic center in Lower Manhattan. No, I don’t. Most of the opponents aren’t bigots but well-meaning worriers — and during earlier waves of intolerance in American history, it was just the same.

Screeds against Catholics from the 19th century sounded just like the invective today against the Not-at-Ground-Zero Mosque. The starting point isn’t hatred but fear: an alarm among patriots that newcomers don’t share their values, don’t believe in democracy, and may harm innocent Americans.