The ONLY reason to insist on a separate name for the same thing is to mark those who must use the new term as inferior.
And it *is* the same thing. Legal marriage, in this country, is a union of equals, and the *relationship* between a gay couple is the same type as that between a mixed-sex couple. So there's no legitimate reason not to treat it the same... including one of the biggest rights of marriage, which is the terminology itself.
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