Hah! Tell that to all the guys in Viet Nam that had it done to stop the misery of insanely itching jungle rot. No, they were not forced to do it, and the results were a clear validation of a very good reason to have it done.
I haven’t seen a study that corrects for socio-economic factors, but I know that, as in so many cases, correlation does not equate to causation.
Also, post #11 mentions prevention of several diseases that are also preventable by celibacy, monogamy, and just plain good hygiene.
Other than Old Testament teaching, I still have a hard time finding a good reason for doing this.