I'd say that the right of the individual is enough reason. Some people who were circumcised against their will don't want to be, and that's reason enough for me. We don't allow earlobe stretching, scarification, tattoos, etc on children, so why should we allow circumcision?
Except it is not. The right of the individual does take precedent when their is harm without benefit. In the case of circumcision, there is benefit. Is it worth the harm? IMO, no. But no enough that a reasonable person would not disagree with me, and what is more- I understand that POV. Thus, I support that individual in making life choices for their family.
I notice that you hedge the choice in permanence. And I understand that you are talking about physical permanence. But, experiences are also permanent and can permanent emotional, cognitive, social, and even physical effects. I absolutely think that my parents should have taught me Chinese. Because I missed a pivotal window in brain development, I will never be able to hear or speak Chinese perfectly. "This is permanent damage they have caused me. I am permanently disfigured and can never experience life as fully because of their intentional and mindless abusive choice."
That is the argument that I keep hearing from some anti-circumcision crowd on these threads. There is another group who take a more even keeled approach wherein they focus on the unnecessary nature of the procedure. This side has very good points that should convince many not to circumcise their sons. Unfortunately these are not legal arguments strong enough to overcome either parental rights or religious exercise. Is it anti-Semitic? No- at least, I don't think so. But suggesting legislation? If I suggested it should be illegal to baptize your baby with submersion, or that it should be illegal to wear necklaces (including crosses) people might accuse me of being anti-christian. I could talk about how submersion in baptisms causes the baby to cry and they obviously suffer a shock to their system. Or I could talk about the dangers of wearing necklaces and how people don't really need them. Would those arguments be anti-christian? No. But, I don't think it would be completely shocking if someone said I was anti-christian for trying to pass legislation that prevented them from following religious practices- unless I had a very good reason.
You mentioned earlobe stretching. If I knew that getting my plugs for my kid would prevent ear infections and make ear cleaning easier, I would be on it like white on rice. Do ear infections need to be prevented in a way different than tubes, medication, and natural immune defense? no. But, different strokes for different folks. I would assume that many people get their child circumcised because it makes cleaning easier, and their child will likely suffer less UTI's as a result. Another group probably largely does it for aesthetics, and another for tradition. I would hope they look at the risks and decide if the risk is one to take. Those that do- are well within their rights. Parents must assess risk and make decisions.
When a friend of mine was pregnant she brought up circumcision. She told me that her dad was a Doc in the military. She told me that her father told her if she had a boy she should get him circumcised- because of the number of guys that he had to circumcise in the field because they had developed horrible infections. He convinced her because he told her that the healing time is better for babies, the pain is less and it is better to get it done where you are guaranteed the safer environment. She had a girl. But there are plenty of guys out their I am sure that were wishing their parents had circumcised them early on when they had to face the knife later. My point with this story is that the arguments just go back and forth- And at the end of the day it is roughly a wash. Unless something new comes to light or we alter our societies thinking- we simply do not have the right to step on parental rights or religious exercises.