Any argument that can be made against same-sex marriage is completely invalid. You cannot argue that it is a sin because our country was founded on religious freedom and if we allow religion to continue to take away a group of people's right to marriage then that is not religious freedom, that is allowing religion to dictate something that not everyone in the US agrees with. If something does not harm you then how is it fair for you to take away someone's right to a happy marriage with the person they love. It is complete ignorance to argue against such and is the same scenario as saying people of different races may not wed, which I'm sure quite a few of the people who are against gay marriage still feel the same way about that issue as well.
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