Donald Trump's bizarre performance at a rally in Fort Dodge, Iowa, on Thursday night — insulting his opponents, swearing, inviting someone to try to stab him — has prompted a new round of "has he gone too far" questioning. (Which is somewhat unusual: The media, which asked that question repeatedly in July and August, is now much more timid about speculating on Trump's political demise for obvious reasons.) It is perfectly possible that he has Gone Too Far™, at long last — perhaps because his tone was noticeably different (as Jeff Blehar of the conservative blog Ace of Spades notes).