No effective preemption has ever been devised to keep an idiot from taking to a microphone.
That is not true. If you had said
“No effective LEGAL preemption has ever been devised to keep an idiot from taking to a microphone” I would agree with you, however history (even American history) is replete with peoples rights to free speech being denied through threats and initimidation, arrest and being held as long as possible until charges need to be filed, “accidents” and outright assasinations.
Let me make it clear that I do not condone any of these methods, because I find them as heinous as the idiot taking the microphone. Silencing political foes is an art form in most communist nations, and our desire to protect and maintain freedom of speech, no matter how offensive, is one of the primary reasons America has been the bastion of freedom to the world.