I guess I am remembering it wrong but I thought sticks and stones were dangerous but words could never hurt me. (Calls to action dont hurt me either, but I can see how one could categorize them as dangerousness due to the resultant action)
Words inspire action. That's why it matters. To paraphrase the Supreme Court, the problem with shouting fire in a crowded theater isn't the shout, it's the dangerous stampede that follows.
And those who deliberately inspire violent behavior with their speech are very, very careful to make sure it's not an explicit call to action. This is not new. "Will no one rid me of this meddlesome priest?" has been around for a long time.
