It is. Infant circumcision in the United States of American, Home of the Free and Land of the Brave, is a violation of Federal Law.
Specifically, if you circumcise an infant in the United States it's a violation of 18 U.S. Code § 116 and you can go to prison. The punishment is 5 years in federal prison. Even if you transport the infant to a country where circumcision is legal you are in violation of 18 U.S. Code § 116 and can spend five years in prison.
Here is the link to the Cornell Law School website where the code is listed https://www.law.cornell.edu/uscode/text/18/116 (my virus checker says the Cornell Law School site is virus free). You can read the black letter law yourself.
Did I mention that the US law forbidding the removal of any part of an infant's genitals applies only to females?
Sad isn't it?