Superficially it's a problem if homosexuality is genetic - if the difference between people's sexual preferences is genetic - because at least a pure homosexual would be unlikely to reproduce and therefore pass on the genes. So the first question you ask is, is it actually genetic, and the answer is probably to some extent yes.

If Bush and Blair are eventually put on trial for war crimes, I shall not be among those pressing for them to be hanged.

I suspect the reason is that most people [...] have a residue of feeling that Darwinian evolution isn't quite big enough to explain everything about life. All I can say as a biologist is that the feeling disappears progressively the more you read about and study what is known about life and evolution. I want to add one thing more. The more you understand the significance of evolution, the more you are pushed away from the agnostic position and towards atheism. Complex, statistically improbable things are by their nature more difficult to explain than simple, statistically probable things.

You can never be absolutely certain that anything doesn't exist. But you can show that it's unlikely.

If complex organisms demand an explanation, so does a complex designer. And it's no solution to raise the theologian's plea that God (or the Intelligent Designer) is simply immune to the normal demands of scientific explanation. To do so would be to shoot yourself in the foot. You cannot have it both ways. Either ID belongs in the science classroom, in which case it must submit to the discipline required of a scientific hypothesis. Or it does not, in which case, get it out of the science classroom and send it back to church, where it belongs.

Or why it is acceptable to train fast runners and high jumpers but not to breed them. I can think of some answers, and they are good ones, which would probably end up persuading me. But hasn't the time come when we should stop being frightened even to put the question?

Faith can be very very dangerous, and deliberately to implant it into the vulnerable mind of an innocent child is a grievous wrong.