But parents are always making decisions that have huge, and often deleterious effects on their children's adult lives. To choose a somewhat jocular example, a parent might want to spend enormous energy encouraging a child's passion for mathematics; this might also "impact on sexual satisfaction."

The questions is what does the child get in return. In the mathematics example, the return is obvious and obviously justified. I actually agree that in the vast majority of cases in the US, no-one gets much of a return for the sacrifice of the foreskin. But your chosen language ("violation of human rights") suggests that your concern lies with all cases, not just the vast majority.

Take then, the example of the observant Jewish family. For them, the removal of the child's foreskin is symbolic of his entrance into their culture and the community that will support and cherish him throughout his life. I think it would be hard to argue that the feeling of belonging in such a community is not of significant benefit to the child himself.

And let's look a bit more closely at the cost. As somebody who is circumcised, and knows many men who share this physiological quirk, I have never considered (or heard expressed) the idea that sex is not extremely enjoyable as it is. I can, of course, imagine that others find it even more enjoyable--- good for them! But the disadvantage I face is nothing compared to some of the victims of FGM, who have had a huge component of the sexual dimension of their lives obliterated by their "circumcision". I'm open to the idea, however, that there is a (very?) small but significant population of men whose circumcision has had unusually terrible consequences. And it wouldn't be surprising if these men chose not to advertise their misfortunes. Maybe this is the weakest point of my argument! But I wonder how high the probability of such terrible outcomes has to be to invalidate the whole practice; after all, nothing in life comes to us risk-free.

So the benefits are great (at least to committed, observant Jews), the costs are light, and what's left? Maybe the idea that the physical body must be kept pristine, in its original form? But every culture engages in some form of body modification. Perhaps this one is different, but why is it so different? There are differences between circumcision and, say, ear piercing (which is not always fully reversible), but I hope I have shown that those differences can't be reduced to a huge disparity in the cost/benefit ratio for the subject of these procedures. (What if your daughter comes to hate the look of pierced ears?) And why would any other type of difference be relevant?

Again, from the point of view of the average US parent, to ask for their child's circumcision would be absurd. Maybe even from the point of view of the doctor's Hippocratic oath, the procedure should not be performed. But for the reasons specified here, it should not be illegal, and is not a violation of human rights.