They might have thought that a person had a right to do it, but didn't have the right to expect to come away unscathed...there was a time when society would not have tolerated such activities, now it fosters them.
You may be right. In a day where people would sometimes be tarred and feathered by their fellow citizens, it makes sense. That said, we can be certain that the Framers had a narrower vision of what constitutes free speech than our current society does. The changes in how the law handles pornography is enough to make that case.
Phelps and his and of swine will face justice, and it will go badly for them. I wouldn’t want to have to explain to Jesus why I thought I was serving him by insulting these families, and they WILL have to do that.