Marriage is simply a legal contract. Gays should be given the same right to establish that contract as the rest of us with the understanding that churches are under no obligation to condone homosexuality or perform gay weddings.
If that is all it is, mankind is doomed to extinction.
We once knew what marriage is. We have become deaf and insensible to the meaning. That's also why abortion is widespread and fatherhood is marginalized.
It's not just a contract. It's an adventure.
That's what the radical gay lobby would have you believe. Marriage is much more complex than simply a "contractual agreement between two people".