“When a crazy man has walked into a Holocaust museum and shot the security guard, maybe that’s an appropriate time to warn people: you’ve got a crazy person in your life, keep an eye on him,” he said in an interview in his Manhattan office last week.

Mr. Smith said he fully anticipated one result of those comments: the nasty e-mail increased.

“Thousands of them,” Mr. Smith said. “And I know they don’t mean the things they say. I know they don’t hate me and want death on my family.”

What they mostly say, he explained, is: “You don’t belong there.” Mr. Smith paused a moment before adding: “I do belong here.”