Okaaaaaaay...so what? There's also bisexuality, pansexuality, etc.<quoted text>
It is because the human race has come to realise that homosexuality isn't a mental disorder or a disease (note that a lot of people still think it is)
"Entitled"? No one need gov't sanction to "find a partner for life".and that as living social beings they're entitled to find a partner for life.
Marriage acknowledges the union of husband and wife, which the state recognizes and privelges.Marriage celebrates this accomplishment.
Social progress doesn't change the facts of life, and biology, nor the state's interest in marriage as a union of husband and wife. We don't put urinals in the women's locker room in the name of "social progress". Some things just don't proh gross.All those things (slavery, religious persecution, etc.) are pertinent for comparison because they represent the same type of social progress. Sorting out authentic right from genuine wrong.