The Presidents Gamble

I'm trying to figure out how allowing gay marriage lessens heterosexual marriage? Its an objection I've heard, and one that doesn't impress me one bit. I've been married for nigh on fourteen years, and I'm a fan of the whole traditional family unit. My wife is lovely, the kids barmy, and the dog is a basket case. We're a chaotic unit, and we have our friction, but aside from all the conventional temptations we've thus far steered the ship on a consistent forward course. How is allowing gay marriage going to compromise, threaten, or usurp this? Just what is it that the religious right in America is afraid of?
At present they are deeply unhappy bunnies because President Obama has finally come out in support of same sex institutions, taking a brave yet I suspect calculated risk. Interestingly, the majority of young Americans support his position, which bodes well for the future. Hopefully the religious zealots will  simply fade from the market place of legitimate ideas in due course, and tomorrows leaders will wonder why so much time was spent on this non issue.
I support strong relationships. Heterosexual, homosexual, I frankly care not. Good relationships are the bedrock of society, and we see what brokenness does to those caught up in it. I really do not understand why so many hours have been burned up concerning ourselves with this, although I do have my suspicions. As always, the core opponents to gay marriage are persons of religion, those who think that reading one two thousand year old book beats reading lots of modern ones. As Mark Twain so famously observed, religion will always oppose progress, and only when they've failed to impose their Monty Python silliness do they join the procession at the back of the line. For me, to support gay marriage does nothing to devalue marriage itself.  It merely extends privileges that I as a heterosexual male already enjoy. That your holy book causes you to hold fast an array of ugly ideas is your business as a person of faith, but please do not seek to inhibit the rights of others based on such a sub standard set of ideals.