I think my views on this as a bible-believing Christian have been expressed very well by other posters in this thread.
I'm really interested in understanding the views of the atheists and agnostics who have taken what I believe are some surprisingly strong positions on this.
Not to take this too far off track, but I'd be interested how they define the term "adult" and why that is an absolute definition for every person and every culture. I'd also be interested why they believe society absolutely "should be" built on expanding freedoms?
I guess where I'm going is I've always assumed atheists/agnostics believe this universe is ultimately some type of randomly occurring cosmic accident with no transcendant meaning or purpose. Coming from that framework, I've been curious how they can make statements that some things are "right" and other things are "wrong." What is the origin of this right/wrong framework? And specific to this debate, why is expanding marriage to homosexuals absolutely the "right" thing to do for ours and every other culture?