There is extremism and there is radical extremism. Is it about gay marriage or no marriage. There is an agenda. It helps to know what it is. Many times the actual goal is not to modify the institution but to actually destroy the institution of marriage.

Masha Gessen has more in mind than simply “expanding” marriage rights in the United States to include homosexual couples. At a panel discussion for the Sydney Writers Festival in 2012, Gessen noted: “I agree that we should have the right to marry, but I also think equally that it is a no-brainer that the institution of marriage should not exist. . . . Fighting for gay marriage generally involves lying about what we’re going to do with marriage when we get there, because we lie that the institution of marriage is not going to change, and that is a lie. The institution of marriage is going to change, and it should change, and again, I don’t think it should exist.” 

Source here.