It probably is protected speech, but there are lots of ways to combat it. The first would be to have a group ready to mix in with them with large signs to over overshadow them. It would be great if the other churches banded together and had a group ready to mix in with them and start singing hymns. Better yet would be a band that lined the streets anytime they showed up and started playing over the army song over the top of them as groups came and went. If they were shouting loud enough to be heard on the actual funeral grounds, I think I would sue them for taking away my right to enjoy my own property. They are, in my opinion, violating with the owner of the property where the funeral is taking place from having "quiet enjoyment" of his property and are in fact creating a legal "nuisance". Sue each and every one of them individually. At the same time get an injunction.

The worst thing that can happen is for the media to keep showing them and giving them a voice. I say attack swiftly, quietly and with a huge legal hammer.