A mentally unhinged man slipped past security at the Republican National Convention last night and delivered a keynote address before he was subdued. The man ranted incoherently on a variety of subjects, frightening many in the national television audience as security officials plotted their next move. We thought if we let him blow off some steam, maybe he would go quietly, said the security spokesman Harland Dorrinson. But he just kept shouting. I thought he was going to chew someones face off. After the man was subdued with a tranquilizer dart, Presidential nominee Mitt Romney said, I hope he gets the help he needs, adding, Having said that, Im going to repeal Obamacare on Day One. The entire incident has left the security staff on edge, Mr. Dorrinson said. A crazed individual breaking in and giving a nationally televised speech is a once-in-a-lifetime kind of thing, he said. But it could happen again tonight. 