Quite honestly, these guys are very clearly inviting violence. There really isn't any question in my mind that they want a full-on, violent confrontation. I only wonder at how they will weep to law enforcement (many of them former MPs) when someone pulls a pistol and begins shooting.
I believe that it is the policy of this forum to disallow comments that would endorse any violent or unlawful act such at the one you are imagining. Your neutraility and restraint are admirable and, I belive, conform to the requirements of the forum.
I, myself, can make no comment on how I might feel in the scenario that you mention because I fear I might lack your restraint.
I don't know -- Phelps himself is reported to be in "frail" health, and his "demonstrators" are mostly women and kids. That's probably why this group doesn't get the beat-down they so richly deserve.