[Hugh the Scot]

"Yelling fire in crowded theater"

This is NOT a limitation on the First Amendment, It's an example of "actions have consequences". It's perfectly legal to yell "FIRE" in a crowded theater so long as there is a fire.
It's the lie that's illegal, not the yelling...

[reasonisfaith]

You make a good distinction, one that furthers my point.

Terrorists hiding amongst members of a particular religion are perpetrating a similar crime and therefore don’t have the protection of the First Amendment.

Even if they’re citizens on American soil.