Strong security controls are needed to protect the central data bases. Many web pages are dynamic, and the content is refreshed often. Surfers want the latest and greatest information, not last month s news. Care must be taken to synchronize the html, http server and cached clones so that traffic is routed to the proper server. If the cloned sites at the caches are indexed by search spiders, subsequent searches can find multiple copies of the same pages.
Surfers can t tell the original from the clone and can locate erroneous or old information.
Cache-servers can easily become unwitting distributors of pornography. At the regional and national levels, caches provide a potential for single point of censorship dictated by the reigning power at the time. As the Web becomes more commercial in nature, and as more and more private information is stored and moved across international boundaries with little constraint, the problems associated with national and regional caching becomes more obvious. It seems obvious to me that if the problem is a lack of bandwidth, then the answer is to add more bandwidth, not add a bandaid bound to bleed.