I'm having a problem accepting that free speech can cover a clear menace. The outrage against their words isn't a side effect of what their beliefs, it's a reaction to their direct message. These people pick and target families solely so they can mentally terrorize them. What they're doing isn't even really a protest. To me, that's not using what is protected under the First Amendment, that's abusing the First Amendment.
Yes, a sad abuse; their words may be menacing, but they are not threatening (from what I seen) nor do they resort to any physical acts. In fact, they follow the legal pathway to their protest licenses.
Its important not to re-think a law of the land based on a few nut jobs. Its important to remember why most of develop world embraces this idea; what history we went through to get it; and what is allows to us to do today.
EDIT... To us, yes, it is clear they are terrorizing, but to them they are doing god's work which opens up the discussion to freedom of religion. They are using legal means to follow their beleifs, despite how diabolical the words are to us. Until they start using force or threats, they MUST be allowed to protest.
This is a very important core tenant of western civilization. Take it from an immigrant; this IS your pride and joy. Don't bend the rule for a few crazies.
EDIT 2 - Would you guys have the same disposition for Scientologists? It is completely obvious it is a scam; tricking people out of their money. They are far more "menacing" than the WBC who really only protests. When we see them we smirk and continue; yet they are gaining a large following with a large expense account. I would hope you guys take your battle against Scientology first.