M. Dodge Thomas: “Some gays and lesbians I know report a similar experience of instantaneous and vivid experience of attraction to members of the same sex, and I’ve no reason to suspect that their experience was any less “authentic” than my own.”
I’m sure pedophiles claim the same thing - that they are genetically predisposed to desire little kids. Yet almost anyone with common sense would see it as an unhealthy and dangerous lifestyle.
The objection to pedophilia is not that it's an inherently "unhealthy and dangerous lifestyle", were it legal it might in some senses (for example, the risk of contracting sexually transmitted diseases) be a more healthy and less dangerous lifestyle for the adult participant than having sex with other adults.
The objection to pedophilia in our culture (and this is not apparent as a matter of "common sense" judgment in all cultures, BTW) - be it between members of the same of the opposite sex - is that it is impossible for children to give informed consent to participate in such behavior, the inherent power differences between the participants are too great.
In one sense this a tragic situation for the pedophile (if they act ethically, they will be in a state of constantly unfulfilled desire), but if they wish to be participants in our culture they have an ethical responsibility not to act on their desires no matter how great the temptation.
However this is just one example of many such constraints on sexual behavior related to great disparities in power, and in this regard the definition of ethical behavior is constantly evolving.
For example very few people would argue that a judge could ethically have a sexual relationship with the defendant appearing before her in a capital murder case, OTOH under what conditions sexual relationships are acceptable between people employed at different levels of the same organization is a question on which opinion is often uncertain and currently in a state of flux.
What is similar in the case of pedophilia and homosexuality is that part of many people's distress in encountering accounts of either is that they "cannot imagine" the mental state of one or both of the parties involved
What is dissimilar is that (at least to me) it's possible to imagine a homosexual relationship which would be ethically superior to its heterosexual counterpart, but I can't imagine any situation in which a sexual relationship between adult and someone with an absolute minimum age of 14 or 15 (and a few years older, in most cases) could be conducted in an ethical manner.