i) One popular argument (if you can call it that) which routinely crops up in debates over "marriage equality" and the like is the claim that since sexual "orientation" isn't chosen, it's unfair to discriminate against LGBT individuals.
ii) Of course, the claim itself is hotly contested. Part of the problem is that it's ambiguous. For instance, a junkie may have an uncontrollable urge to shoot up. He can't help himself. And there's a sense in which he didn't choose to become a junkie. He did, however, choose an addictive behavior.
iii) How, let's grant, for the sake of argument, that homosexual orientation is inborn and irrepressible. Even if that were the case, does that, of itself, justify equal treatment?
Suppose an ex-Marine develops brain cancer, which makes him sociopathic.
BTW, this isn't just hypothetical. There's a real life case (Charles Whitman):
Suppose he barges into an elementary school with a machine gun and a backpack full of magazines to reload. He plans to kill every child in sight.
Before he starts his shooting spree, police arrive. As a police sharpshooter is scoping out one side of the school, our would-be sniper steps in front of a classroom window, giving the sharpshooter a clear shot. Should he take the shot? Should he cap the would-be sniper before he starts killing little kids?
Technically, if the sniper kills the kids, that isn't murder. In his mental condition, there's no criminal intent. No malice aforethought. He is not morally responsible for his actions.
But even if it isn't "fair" to shoot him, it isn't fair to let him kill little kids. Although he's a raging sociopath through no fault of his own, he needs to be stopped by any means necessary.
Likewise, in an episode of La Femme Nikita ("Imitation of Death"), there's a terrorist organization that kidnaps children to turn them into suicide bombers. For years they are brainwashed and brutalized to make them cruel. They have no conscience. They will kill without compunction.
What should you do if one of them is about to detonate his suicide jacket in a crowded shopping center?
iv) Now, there are people who'd scream: "You're comparing gays to suicide bombers and mass murderers!"
Actually, no. Rather, I'm offering counterexamples to their principle. If someone didn't choose to be the way they are, if they can't help it, does that mean they are entitled to equal treatment?
If anything, if someone lacks impulse control, they need to be treated differently.