You obviously have never been to their website, then. I know, having visited there in the past (I am not sure where it is now, though. It keeps disappearing and reappearing like a cockroach.), they had a manual available to its members on how to get close to, befriend, and molest a child, as well as how to get away with it. In fact, the existence of this manual is part of the plaintiff's case in Curley v. NAMBLA, a $100 million lawsuit pending in Massachusetts (You may have heard of this case; this is the one where the ACLU decided to defend NAMBLA pro bono.).
There should be no question, no doubt, NAMBLA is a criminal organization. So why isn't John Ashcroft investigating them under the RICO statutes at an absolute minimum?