I don't see circumcision as an issue honestly.
You don't see a blatant violation of a persons right to bodily integrity as an issue? Would you also be ok with a parent choosing to cut off their infant's ear lobes, removing their tonsils and removing their appendix straight after birth as well? After all, we can do without them and they might cause problems later on in life, so why not just get rid of them now? It's the same scenario, the latter examples just don't have centuries of dogma reinforcing them.
I've never even heard of anyone complaining about the fact that they're circumsized.
I know a LOT of people who are very resentful that they were mutilated as children without their consent. I also know many more others who don't necessarily have that same strong resentment, but still wish they'd be given the chance to experience what it is like to have intact genitalia as nature intended.
I'm circumsized and I don't really give a shit about it
Whether or not you care that you were circumsized doesn't mean that others don't, and doesn't make it any less wrong. Your parents should not have done that to you, and they had no way of knowing whether you would approve of it or not.
it does literally no harm and makes zero difference in life
Circumcision certainly does cause harm, which you can verify in detail by consulting almost any anatomy textbook. The foreskin contains upward of 10,000 fine-touch nerve endings, making it an erogenous zone which creates an added sensation during sex/masturbation. It also protects the sensitive glans by keeping it moist (preventing keratinization) and shielding it from abrasive damage, among many other functions.
The absence of the foreskin can also affect the manner in which one can comfortably masturbate, as many guys who are cut require a lubricant in order to do so. Indeed, this was one of the reasons that circumcision was championed in the 19th century as it was thought to discourage and delay masturbation, which was viewed negatively at the time. Furthermore, there are many cool tricks such as "docking" and "ballooning" that can't be done without a foreskin, and it provides added functionality during sex. For example, your partner can do things like pluck your frenulum (which is often entirely removed during a circumcision) with their tongue or a finger and swirl their tongue around the inside of your foreskin (feels great, trust me).
Circumcisions can also be botched, and I've witnessed many tragic stories (one of which was from a user on this very forum who I was once close friends with) whereby the recipients of the operation had to live with permanent disfigurement and shame for the rest of their lives. It's estimated that hundreds of botched circumcisions happen every year in the US, which is a sickening number of people to inflict severe suffering upon for no sane reason whatsoever.
Also considering circumcision is mainly done out of religious ritual, it'd be a big "fuck you and your religion" to fight to banish the practice, not to mention it doesn't affect you whatsoever so it's kinda selfish to strike against such an insignificant thing because of your own opinion.
Freedom of religion does not and should not grant anyone the right to impose their beliefs upon anybody else, which is exactly what is happening when somebody circumcises for that reason. Who says that the child will share the same religious views as their parents? What about their own freedom to choose what, if any, religion they subscribe to? Additionally, freedom of religion should NEVER take precedence over the fundamental human rights of another human being, in this case, the right to bodily integrity.
If it was something absurd like child slavery or trafficking or some shit where there's constant suffering, then yes that'd be something that requires immediate action
Mutilating the genitals of defenseless infants absolutely
IS absurd, and comparing it to things like slavery and trafficking is utterly pointless. Our society has already partially recognized the absurdity of it, which is the reason we already have laws in place that prohibit all forms of Female Genital Mutilation, no matter what kind (and yes, there are forms of FGM that are less severe in terms of loss of functionality when compared to MGM and IGM, but all forms of routine cutting are fundamentally wrong for the same primary reasons regardless). Those laws need to be extended to encompass all forms of genital cutting against children of all sexes. It is sexist that our current system only protects people born as female, because everybody should have the right to keep the normal, healthy genitals they were born with.
but something so little like circumcision which is a one time thing (that can't even be remembered anyways due to infantile amnesia, so that experience is a non-factor) that makes basically no difference in the long-term is pointless to me. To each their own, anyways.
Circumcision is not a "little" issue, and it's not a "one-time-thing" either, since it's a permanent body modification that a person is forced to live with for the rest of their lives. So, stop trying to rationalize this vile, medieval practice, and realise that we're talking about the rights of children, who should never have something like this willingly inflicted upon them. Get over yourself and join the fight.