If the group's core values include mutilating infants, and if the group's values widely affect the actions of the population (as is the case in the US), then it

If the group's core values include mutilating infants, and if the group's values widely affect the actions of the population (as is the case in the US), then it is absolutely neccessary to share advice that goes against those values in order to negate those harmful effects. You use "miniscule risks" as an argument - the problem isn't the risks of circumcision, it's the circumcision itself. It is (in majority of cases) a completely unneccesary form of mutilation. It seems to me that your argument boils down to "how dare you tell people mutilating infants is wrong when my culture has been mutilating infants for millenia?". Most people don't circumcise their kids because of religion - and those they do won't listen to this advice anyway.