== Long-term sockpuppetry violates Internet Service Porviders' "Terms of Service" == 

 I have been around here long enough now to see the countless hours put into chasing sockpuppets and their dynamic IP addresses.  As you know, Internet Service Providers have strict "Terms of Use/Service" agreements with their customers.  In these TOS agreements, it clearly states that if the customer uses the ISP services to damage or destroy websites, or for other harassing type of behavior on the Internet, then their service will be terminated.  So, after years of chasing some of these "banned users" here on Wikipedia, I think a good case could be presented to an Internet Service Provider that one of their customers is doing great damage harassing the Wikipedia project and wasting the resources of Wikipedia.  All you would have to show is a history of damage/harassment done by the sockpuppet/dynamic IP and the exact times the IP made those edits identified as vandalism, then the ISP could trace it back to a particular customer and terminate their service.  Obviously this would only be used in extreme cases which have gone on for many months or years. I'm certain someone at Wiki must have thought of this before, so what is the problem with implementing this as policy on Wiki?