I've done research on the Phelps family. They're not as crazy as people might think. Fred Phelps aside from the fact that he was an original fire & brimstone preacher was one of the first people in his state to go up against his state on civil rights matters and was according to legal documents an excellent lawyer. They are just expressing their religious beliefs in a uninterrupted manner. If anything I think they're consistent in their attacks of what they think is a nation that they believe is 'doomed'. They're just more vocal about it.
Regardless of what legitimate baptists say, their position(that of the Phelps family) is not one that is alien to baptist. Do baptists not think gays are going to burn in hell? Have we not had baptist/catholic ministers on television talking about whenever something bad happens in America it's because of our secularism or the fault of gays and lesbians? Legitimate baptists are fooling themselves if they don't think these people are as legitimate in their beliefs as Jerry Falwell or whoever holds the title of megastar in the baptist world. The Phelps family are an "extremist" wing of the baptist world but as far as being illegitimate? Seriously doubt that.