Circumcision is the amputation of the foreskin, not extra skin but an integral part of the penis; measuring 15 square inches in an adult, over half the penile skin, including the most sensitive parts of the penis. The foreskin is packed with nerve endings, special anatomical features like the ridged band and has a unique elastic gliding action, allowing it to slide on itself and act like lube. This action is what most males use to masturbate with. Circumcised males use what skin they have left, except those who are cut so tightly that they have to use lube or just rub it dry. The intact male can stroke the entire length of his penis using his foreskin and also has the option to use lube too, if he wants to. During intercourse the foreskin acts like lube on entry and may act as a dam, preventing lubricating secretions escaping from the vagina. In one study women reported that sex with an intact partner was gentler and more satisfying since he doesn't have to thrust as hard to feel enough stimulation. Removing the foreskin turns the surface of the glans from an inner mucosal membrane to outside skin. Newly circumcised adults usually go through some weeks of intense discomfort as the glans is constantly exposed to rubbing on clothing, until it develops a thicker keratin layer and becomes less sensitive.
Not one major medical organisation in the world recommends routine infant circumcision anymore. The US is the last western nation still doing this to about 50% of its newborn males but even there rates are falling and many insurance companies no longer cover it. Sadly when it is done they don't use anaesthetic or when they do it’s risky and ineffective. It's child abuse, pure and simple.
The penis forms as one organ and at birth the foreskin is usually fused to the glans like a fingernail to its finger. So there is no cavity for germs and dirt to collect in until it separates naturally later, at an average age of 10. Only the boy himself should retract it and then he can be taught to skin back and rinse with plain water regularly.
Misguided attempts to retract too early, often by doctors and nurses, are the main cause of damage to boys’ foreskins and the real main reason for childhood circumcisions.
To perform a neo-natal circumcision the circumciser has to rip the foreskin away from the glans with forceps. Then the foreskin is either cut away or clamped until it falls off. Both methods cause the baby extreme pain and his raw glans and wound sting every time he urinates. It's quite common for the raw edges of the cut foreskin to fuse to the raw glans during the healing process, forming skin bridges or tags. These complications and other more serious ones are often not found till puberty and do not show up in complication statistics.
More serious complications, though not common are immediate. Some babies lose their penis to infection, bleed profusely (often because they are haemophiliac) or even die each year.
The claimed benefits of circumcision are a beat up but medical authorities have worked out that the overall complication rate is higher than all the benefits claimed by the pro-cutting advocates. One by one the claims are disproved but the pro-cutting zealots come up with more and keep quoting the old ones despite the evidence against them. For example you have more chance of dying from a circumcision or losing your penis from wound infection than from penile cancer. The rate of penile cancer is higher in the largely-circumcised USA than in European countries where less than 1% of males are circumcised. The US Cancer Society does NOT recommend routine circumcision.
A study in New Zealand followed a cohort of boys through life from birth to age 32. About 40% were circumcised. The intact males had a slightly lower rate of sexually transmitted infections than the circumcised but there was no significant difference.
Using surgery to mutilate the genitals instead of washing in a modern western society makes no sense. Normal intact male genitals are even easier to wash than female ones and the same substance, smegma collects in the genital folds of both sexes. A few intact males have problems with tight foreskin but this is only a tiny proportion of intact males. The condition can now be almost always treated with simple stretching exercises, sometimes in combination with a steroid cream that speeds up the process.
Any boy born now will grow up with many intact friends and there is every chance he would resent this unnecessary cosmetic surgery.