Problem #1: The issue with progressives is "the numbers." 87% of Americans consider themselves Christian, therefore in finding a religious "enemy" guess who it is? It doesn't matter that there isn't a major religion in the world that supports any form of homosexuality, it's demonizing this 87%.
Problem #2: Any argument we try to level isn't compatible with Christ's teaching. E.g. "God hates homos" (Thank you Westboro Baptist Church). God gives you a choice, follow me or don't. Christ said "...don't judge..." and "Love each other as I have loved you..." and "...remove the beam from your eye first..."
Mr. Thomas is correct, if Christians cannot line their message up to Christ's, in the end, we will lose.