"Common sense" accepts the view that religion makes people better. I disagree. Religion amplifies people. Those with love in their hearts can find more strength to do good in the world. Those who hate things can make themselves believe that God hates those same things just as much. The WBC have done everything in their power to make themselves repellent even to people who may agree with them about homosexuality. Personally, I think they have just taken the Bible and made some verses more important than others.
It's a big book. It's impossible to do otherwise.
Consider Matthew 5:10-11, two verses from the end of the Beatitudes, the list of the blessed from Jesus' Sermon on the Mount. This is often put forward as the epitome of God's sweetness and light and the great comfort to the afflicted of this world.
10 “Blessed are those who are persecuted for righteousness' sake, for theirs is the kingdom of heaven.
11 “Blessed are you when others revile you and persecute you and utter all kinds of evil against you falsely on my account.
There is no question but that Rev. Phelps and his followers believe these verses are meant for them. They have no reason to be meek, because they do not want to inherit the earth. They are not interested in the rewards given to the merciful or the peacemakers. They want the kingdom of heaven, so they want to be persecuted. I doubt they believe their actions will change public policy towards gays. Their own salvation is much more important to them.
There is no part of the Bible that cannot be twisted by someone who is intent on nurturing the hatred that any human being can find in his or her heart with just a little effort.
And so, in my modest way, I have added to the persecution of the Rev. Fred Phelps and his flock, though I do not claim I have borne false witness against them. Let me say to them, you're welcome. If you want to thank me, a fruit basket would be nice.