Though most find the platform of the North American Man/Boy Love Association to be repugnant, forcing them to disband would violate their first amendment right to free speech. Individuals who engage in illegal activities, such as sex with minors, should be prosecuted, but we cannot ban an organization just because it advocates making something that is illegal legal.
I believe the NAMBLA is a group that is trying to legalize minor sex and child rape. They have advocated for pedophiles to be release for no coercion, but children don't understand sex and are easily manipulated. If the mafia and drug trafficking is illegal, so should a group that supports minor sex.