How does circumcision reduce risk for HIV?

Factual Questions
1

This article on Slate.com is actually about how a bunch of anti-circumcision groups, “intactivists” as they call themselves (great name, btw!), shitstormed an Amazon.com listing for a book that has a few pages that are pro-circumcision when it comes to HIV prevention.

I don’t really care about their trolling, this thread isn’t about that. But for the life of me, I cannot figure out WHY circumcision reduces HIV risk. I even read the linked article but it only made some references to possible risky behavior due to beliefs among circumcized/uncircumcized men.

If its simply about behavior, then the solution isn’t exactly circumcision, but people’s beliefs. Because I don’t see how missing a piece of foreskin makes one less at risk for HIV. Its not like that little bit of skin is a magical HIV vacuum. So what’s the deal? Is it just behavior?

2

From what I’ve read…

With the foreskin in place, the glans and the inside of the forskin are more like membrane skin, moist and soft. With the foreskin removed the glans is drier, less sensitive, and the skin is harder.

Anti-circumcision advocates suggest a softer glans is more sensitive, thus us chopped gents are being short-changed in the pleasure experience.

A softer skin is more likely to have abrasions, and micro-tears from vigorous activity, meaning places for the virus to enter the body. Additionally, the foreskin will trap body fluids from earlier action, they don’t dry out nearly as fast, so the virus has more time to enter the body.

Then numbers I have seen suggest uncricumcised men are 2 to 5 times more likely to contract the infection. The same issue also apply to other diseases. Plus, there’s smegma, the secretion that normally accumulates in there - if a man does not wash himself their regularly, he runs a greater risk of cancer.

3

When not using a condom. Those are the 5 key words that get left out of this statement.

4

Hardness of the skin is part of it, but the main reason is that the inside of the foreskin contains cells called Langerhans cells, which are particularly attractive to HIV. These cells are also found in the vagina, incidentally, but not on the tip of the circumcised penis.

5

If both use a condom, the relative risk remains the same. If the condom breaks or leaks, uncircumcised is X times more likely to contract HIV.