I have several family members that are conservative evangelical Christians, so let me attempt to communicate their stance on this issue. The big motivating factor for many evangelicals is to ensure that the greatest number of people make their way into heaven, and the bar for entry is very specific. It seems to me their concern about the erosion of public morality has changed to concern specifically the erosion of Christian morality in the wake of the Supreme Court ruling; hence the vitriol towards perceived progressive denominations.

Now if only I could explain why homosexuality is such a lightning rod with evangelicals rather than shellfish consumption, synthetic fabrics, or usury.

Edit: phrasing

I think that they're right as far as what Christianity says about marriage. However, think they miss the point some of the rest of us have about the law. I just don't find anything in the Bible that suggests that Christians are supposed to impose canons on people who are not Christians. There's no command to impose the Bible, it's only binding on Christians, it's not like Shariah where nonmuslims must be bound by Muslim law.

America isn't a Christian nation, from the very beginning it was founded on the Englightenment, not Anglican law or Catholic law or Baptist law.

If a person is gay, they were born that way and cant help it. Its not some disease to find a cure for. Why cant they get married,if they wish. I don't believe God would punish them for something that they cant help. After all, God made them the way they are.