Recent History of Circumcision

 Americans were one of the first christian sects to adopt widespread circumcision. Christians had previously seen it as a christkiller habit. Like, the whole point of the new testament is to replace the old covenant. I.e. circumcision is stupid, let's stop doing it.

 Apparently this was primarily due to a surge in syphilis. The idea was that men would find sex less appealing, thus engage in less of it. Likewise the sheath was considered dirty, meaning a comforting environment for pests.

 Trying to lessen sex by making it less appealing is like trying to lessen hunger by feeding less. Circumcision makes sex less satisfying, so cut men become hornier in search of sating their desires. Since the call is coming from inside the house, the sex is never satisfying, so they also cheat more, under the hypothesis that maybe their wives' pussies are somehow deficient.
 It can't be because they're cut, since everyone is doing it... Even if it is their own deficiency, why not seek a heroic snatch which can satisfy them despite that?
 They also masturbate frequently. For similar reasons, plus the fact the male hand can apply far more pressure than even the most seasoned kegel-obsessed whore. 

 Likewise, the dryness damages the skin of the head, causing microfractures, encouraging disease spread. The scar tissue, having been catastrophically penetrated once, is easier than normal tissue to penetrate again. The fact it feels less sensitive means it is less sensitive...meaning pathogens are detected later and responded to less aggressively. The sebum secreted by the sheath contains antibiotic peptides. The nothing secreted by an amputation does not.

 Masochism.

 To use the lindy phrase, the purpose of a system is what it does. Americans circumcized their little boys because they like committing treacherous sexual violence on babies, ideally catastrophically traumatic, and ideally on their own spawn. 

 It is not a coincidence that decades of exposure to pedophile school culminated in a syphilis epidemic. It is likewise not a coincidence that a schooled population was easily convinced to practice mutilation.