An organization dedicated to reducing spam tries to get Internet service providers(ISP) in an East Asian country to stop the spammers by protecting their mail servers. When this effort is unsuccessful, the anti-spam organization puts the address of these ISPs on its black list.Many ISPs in the USA consult the black list and refuse to accept email from the blacklisted ISPs. This action has two results. First, the amount of spam received by the typical email user in the USA drops 25%.Second,tens of thousands of innocent computer users in the East Asian country are unable to send email to friends and business in USA.