I wouldn't be surprised if a fed up vet got violent with the protesters; I'm kinda surprised none has, and it's a tribute to the restraint of members of the military, but I've never seen anything to indicate the Phelpses are inciting violence against servicemen. I could see it when they protested at Matthew Shepards funeral, because that was an act of assault, torture and murder they seemed to condone. It doesn't seem like they're advocating violence against soldiers though. Perhaps an argument could be made that they're endorsing the death of soldiers, but otherwise I don't think this is on the level of shouting "FIRE!" in a theater.

Which really really sucks, but we're once again back to the principle that popular speech doesn't need protection. I hope there's some legitimate legal wrinkle here that I'm missing and the Justices won't, but I'm not optimistic.