Parents aren't allowed to give their babies face tattoos or cheek piercings just because they find aesthetic value in it. The right to your own body should be ranked higher than the right to do unnecessary and permanent procedures on children who can't consent to them.
I beg to differ. Perhaps not in your culture, but in many other cultures and regions people engage in various types of body modifications. In these regions it may very well be the norm. Likewise, there are cultures which have been circumcising their boys for thousands of years, to them removing the foreskin is trivial and necessary. Just like you may find the removal of the foreskin shocking, in these cultures having a foreskin is outlandish, and while I do not expect you to agree with their sense of aesthetics or traditions, you are going to have to try to appreciate the fact that what you consider shocking and what they consider shocking is simply reversed in this case.
It's not about robbing people of their rites of passage, but rather about protecting the rights of children.
Again, I beg to differ. It is a classic case of moral superiority over appreciating the fact that we live in a world with different people and cultures who are sometimes radically different from each other. There is no possible way that for example we can go to a Pacific island and tell the people that from now own they cannot apply body art because by the values of our culture it is considered barbaric.
Many circumcised men (about 20% iirc) wish that they weren't circumcised, and that is reason alone to ban it.
I'd like to see the study in order to learn more about it. Which country (countries) held the study? which cultures were surveyed? were the circumcised men part of a certain culture? why was circumcision preformed on them? etc.
Once a person is 18, they can get circumcised, get a full body tattoo, stretch their earlobes or stick needles through their cheeks, that's their right to their own body.
This is social relativism and ignores the cultural contexts of these practices. If a person would get a choice at 18 to preform such practices not only will these practices lose their effect, but by that time it will be abuse of a child who grew up differently than his native culture, and denied being part of it. Against his will to boot.
FGM is, of course, much worse than an ear piercing or male circumcision, but neither of these processes should be allowed to be done on children who can't consent to them.
We will agree to disagree. I would not presume to expect you to circumcise any future baby boy you may bring to this world but to work from your personal and social norms, likewise I'd like to think that my sensibilities and those of my culture are not going to be excluded either.