Well, it depends on where you live. Many states don’t allow civil unions — which I consider to be a freedom the same as marriage. Even with civil unions, there are other such as granting spousal privilege in legal matters. So at a federal level, they are not.
“many states don’t allow civil unions.”
True, and in those states, neither gays, nor straights, nor polyamorists, nor cousins, nor polygamists, nor celibates, can enter into a civil union.
It’s not just gays who can’t enter into a civil union in those states. The law applies to all of us.
In states where homosexual marriage is outlawed, I can’t marry another woman. Or my brother. I can’t marry a man who already has a wife, either.
The laws applies to all of us, equally.