It doesn't bother making sure that you're alive to say it.
It doesn't bother making sure that you're capable of saying something worthwhile.
So, yes. You have freedom of speech. It's just that most American speech is pointless.
I am an European, but we have a long way to go towards sanity. And with obesity declared a disability I feel like we are moving away from it.
Indeed, having speech and naught else is like a vent that lets off steam, making change and better lives harder to come by. It is the fool's prerogative to speak his mind, but at the end of the day, the king is still a king, and the fool is still a fool.
Take the instance of the Robin Hood Airport Twitter trial -in the US you'd be relying on a public defender to make a 1st Amendment argument - win and you're grand, lose and the American justice system would bury you as a terrorist.
The US might not be perfect (who is?) but it offers some of the highest levels of protection for an individuals rights of any country.
Europe is not big on the whole freedom of speech stuff.