So then, we have established that homosexuals can both engage in the sexual act, and procreate.
So, what reason does the government have to disallow civil marriage licenses to same sex couples?
What is this, a word game?
The sexual act between two persons of the same sex can never produce an offspring and that is why it makes sense to define marriage as the union between one man and one woman. This is not rocket science. This is the way it has been for hundreds and hundreds of years. Science and certain social developments have not changed the fundamental facts of life.
Men and women having sex can produce offspring. To preserve our liberties and our civilization, it is a necessity to regulate that process. Two persons of the same gender having sex cannot produce offspring; therefore we have no need to regulate it.