Let me lay my cards on the table at the outset and say that it is not only my belief, but my absolute certainty, that homosexuality is an aberration. This does NOT mean that I believe people who are homosexual should be persecuted; they have the right to exist just as does any individual who is pulling their own weight and not infringing on anyone else's rights. In this country, the United States, a person has the right to be wrong as long as he is not coercing or hurting anyone else. And, in case you missed my point above, homosexuality is wrong.
How can I say this? Let's reason it out together.
Once all of the niceties such as romance, courtship, bonding, etc. are stripped away, human sexuality is for one purpose and one purpose only: procreation. Flowers, candy, long walks, long talks, gifts, cooing and cuddling are all just preludes to the need to perpetuate the species. Yes, sex is fun, but it's fun because it has to be to maximize couplings and create the next generation. Heterosexual sex is, therefore, natural in that it follows biological correctness. Yes, there are some practices that heterosexuals engage in that lead to a procreative dead end (birth control, sodomy), but, in general, heterosexuals are on the right track.
Homosexuals, on the other hand, are a procreative black hole. Their sexual acts do not, and cannot, ever, contribute to the perpetuation of the species. The sexual actions they engage in are not in accordance with nature, hence, their actions are unnatural. If something is unnatural it means it is so against nature that it does not contribute to the advancement of the species and, in fact, is against the species. So, homosexuality, as both an act and a philosophy, is anti-human.
Over the last generation or so, there has been a persistent cry from militant homosexuals that they did not choose the way they behave sexually, but that they were born that way. Scientifically, although there has been no physical evidence yet found to back up this claim, the jury is still out on a final ruling. With the human genome project now complete, it should only be a matter of time before a homosexual gene, if it exists, is found. Should a gene be found that really does cause a person to be homosexual, or at least have a proclivity towards that behavior, perhaps the parents of an unborn child found with this gene would elect to abort him or her.
Oh, I can hear the outcry now of militant homosexuals to that course of action. "It's genocide against homosexuals [only they would use the asinine term 'gays']! We're being persecuted for who we are!" I would have to say to them, "No, we now have the knowledge that homosexuality is indeed a birth defect, no different than spina bifida or Down syndrome, and we can begin to eradicate it from the population. If you don't like it, perhaps you should join with the Christian right, if they'll have you, in an [unholy] alliance against abortion." What a hoot THAT would be.
But what if homosexuality is a choice and not genetic? The human mind is the most complex piece of machinery in the universe; who knows what subtle and not-so-subtle influences it is exposed to cause it to choose certain paths, especially in a young, developing mind. Just to reiterate, I am not for persecution of homosexuals, but neither am I for the promotion of it as just another lifestyle (deathstyle, as some wag once said, is closer to the truth). If adult folks choose to be that way, that's their business, but I will never consider it natural, nor will I ever teach my child that it is anything but an aberration.
In the end, this debate on what causes homosexuality really is pointless. As I laid out above, whatever its cause(s), homosexuality is anti-life, and that's reason enough to oppose it as wrong.