LOL...cut it off! Cut it all off...in the name of "cleanliness" just lop the thing to bits. LOL
Anyway...think on this....the foreskin protects the head of the penis. Though I am not a man I should think that any man would understand that this makes the head of said penis more sensitive than one that has had the foreskin cut away as the head then continuously rubs against the clothing...desensitizing the head of the penis.
So you aren't just depriving your son's the opportunity to decide/value their whole body, you are inflicting pain (yes even though most of the time it is done to an innocent, helpless baby who has no say in it , it does hurt them) AND you are depriving them of a more intense, sensitive sexual experience in the future.