He's American, it's standard practice here because the guy who invented cornflakes thought it was a good idea.
That's the
cover story
. The
real reason is
that after WWII, when it really became common practice, it was to make it harder to tell who the Jews were among the general population, and this was a time when a larger number of medical practitioners in the US were indeed Jewish.
As far as any benefit it has, all the original reasons they made up for why it was a good idea were all wrong. After decades of studying the issue the only benefit that has been discovered is that there is a slightly reduced risk of transmitting HIV to a female sex partner of around 13% and the reasoning behind it is rather complex, involving the immune system, macrophages, etc... so I won't bore you with the immunomolecular details.
So, this generally means that there was no benefit to circumcision until the late 1970's early 1980's when HIV was
introduced by the CIA to try and kill off the queers, drug users, whores, and niggers, introduced to the wider world by a Northern European laborer that brought it from Kinshasa in the Congo because of his love of prostitutes, with the prostitutes likely being infected by raw dogging Congolese men that ate bush meat (
or fucked animals that were members of the great ape family). Also, that means it provides no benefit to anyone that isn't fucking guys that
raw dog queers, drug users, whores, and niggers. have HIV.
So, in a rather roundabout way, the benefit of circumcision and the introduction of HIV as a result of fucking whores, are tied in a very tenuous way to The Story of Rusty "The Whoremaster" Greer.