> It is not so much the result of both that I find problematic as the painful methodology by which they are achieved.

Sure, that is something to discuss. In the case of teeth, most parents in most of the world only have their children go through procedures that are likely to be important for their health (even if the child may not like the procedure). Male circumcision is also not something I condone personally, and it is relatively rare in most of the world outside some ethnic/religious groups.

> It has been well discussed and noted that physicians seem to be far more willing to perform elective sterilizations on males than on females and find some kind of greater moral fault with the latter than the former.

We are discussing forced sterilization here in general. When you are talking about male elective sterilization, do you mean vasectomy? Because then, one reason why surgeons may be more willing to go through with it is because it is (at least theoretically) reversible, so it constitutes a smaller decision than surgical female sterilization, which is always definitive.

It is also true that historically doctors have felt far more entitled to make decisions for women's bodies than for men's, so I do expect that this shamefully persists.

> So yes, I consider removing a man's reproductive capacity to be quite trivial and inconsequential compared to removing his eye.
> Which of both would you choose?

This is not about choice - that is the whole point. The population we are talking about is not given any choice - the state is deciding to change the way their body works, against their own interests.

Even more importantly, while taking away someone's reproductive capacity may be a smaller apparent harm than taking away their eyes, it is a much, much worse harm over the long term of the community. Literally destroying the Family as a core part of their community is going to destroy their old age, and it is an explicit attack on their culture.

> It's telling that human beings willingly surrender their reproductive capacity all the time, but I have seldom heard of a man who decided to have a healthy eye removed simply because he wanted himself rid of it.

You will find very, very few human beings permanently surrender their reproductive capacity willingly EXCEPT for those who are essentially finished with it - people with at least one, but likely several children. True, there are likely slightly more people who willingly permanently give up their reproductive capacity than people who have an eye removed, but the reason is also obvious: there is absolutely nothing to gain from having an eye removed, while giving up your reproductive capacity allows you to have unprotected sex without the possibility of expensive, hard to care for children.

> And what test or criteria might you use to decide what is and isn't a “fundamental function of one's organism”?

There are many ways to come up with a definition that will include reproduction but not include crooked teeth or the foreskin. In fact, reproduction is so fundamental that we usually define life as being primarily related to reproduction - that is, any chemical substance that can simply reproduce itself is usually at least a candidate for being considered a form of life (the minimalist definition is just a fixed physical form and reproduction + heredity).

So while many functions of a living organism are more or less "fundamental", reproduction is almost the only one you can't debate away.

Now, if looking strictly at one individual organism, it is true that reproduction becomes much less fundamental, so I am assuming that this is the angle you are thinking from. But I don't think this is the right way of looking at it when considering whether a medical procedure could be justly forced on an entire population.