There is quite a difference between the real danger posed by a fire in a crowded theater and the irrational, emotional reaction of irrational people thousands of miles away to nothing but words or images.
If speech in the US must be limited by how irrational nutcases in any part of the world might react, then we are allowing the most irrational people on earth to determine what our freedoms should be.
Might just as well let Rageboy be our censor....