Before we get into all the arguments that have been brought up in the marriage equality debate, I thought I would spend a little time addressing the legal aspects of marriage in America. Rand Paul got teased by the left when he recently said he would support same sex couples getting a contract. I don't know, but he probably said that the contract wouldn't be "marriage," but the law doesn't make that distinction.
From a purely legal standpoint, marriage is a contract. One that has very specific legal consequences. A marriage in law establishes an immediate family relation where one did not exist. As such, the marriage contract affects next of kin status, hospital visitation, parental rights, and tax status among other things.
Now, it is important to discuss how these legal benefits are affected by religious doctrine- below the squiggle:
They're not.
If you believe that marriage is sacred, well, the government has no business in dealing with sacred things, so its recognition of marriage is not sanctioned by G-d. However, if some member of the Clergy decides to give religious imprimatur to a same-sex marriage, the government is equally prevented from saying that can't happen.
I realized long ago that I don't agree with my Rabbi about how to G-d. I also love knowing that I live in a country that doesn't tell me how to G-d. If America became 51% Muslim tomorrow I would not be afraid of Sharia Law because of the Constitution.
I am amused that the very people who wave copies of the Constitution are the same people who fear precisely what it protects. If you think "Freedom of Religion" only applies to Christianity, please see "Freedom of Religion."
If you are eligible to enter into a marriage contract, that is, you are of legal age, human, and sane, you should be able to enter into that contract with anyone else who fits that criteria. Equal protection, pure and simple. If I want to marry another man (I don't), and you don't like it, then you are objecting to my choice, and you are not entitled to have your objections imposed on me.
Now, this does not enable polygamy, which was only outlawed in the late 1800's to piss off the Mormons. It also does not allow someone not named Elaine Chao to marry a box turtle. Animals cannot legally consent. You also cannot marry your sister or your daughter. Remember, it creates an immediate family relation where one did NOT exist.