If all sin were illegal, we'd all be serving life sentences.
Having said that, this manufactured controversy is not about "human rights," but about forcing society to endorse a perverse abuse of the human body. What society in the history of Man has promoted same-gender depravity as legitimate family structure?
The definition of "marriage" is not determined by majority-vote; if it is, what's to keep "We the People" from mis-defining marriage as "one man, three women," "one mother, one son," "one man, one iPod," or "one man, one [insert farm animal here] (pun definitely not intended)? How will anyone be able to stop NAMBLA or Islam from defiling our children (Allah-sanctioned pedophilia, for the uninformed)?
We are not defining marriage, we are merely describing what already exists -- what God created -- and that is a permanent union of one man and one woman (with the glorious possibility of children).
Even the person of no particular religious or moral conviction has to see that homosexuality taken to its ultimate conclusion leads only to the end of civilization and the extinction of the human race.
And it is obvious that the human body was designed with the systems for a man and a woman to reproduce.
Tolerance is not approval. Endorsing sin is not love.