Well, he may be dumber than any other US President, but he's smarter than at least one Roman Emperor, Gaius Julius Caesar Augustus Germanicus, AKA Caligula. Caligula was too slow of wit to disarm the Praetorian Guard, while at the same time behaving like an unreliable, murdering idiot. And the results were predictable, just not to Caligula.
Well, Obama's smarter than that, at least. Ain't no armed Marines getting close to him! Nosiree. Vox Day explains HERE.