When asked about the possibility for a technology to guarantee anonymous online activity for a user Mr. Clarke replies: " It is a cost-benefit decision. One must make the cost of circumventing someone's anonymity significantly higher than the benefit of doing so. Freenet is designed to achieve this in environments such as China and Saudi Arabia and easily achieves this in environments such as the United States."
Mr. Oppenheim refers to the Madster ruling in which the Court of Appeals stated that trying to cover the identity of a copyright infringer by means of technology is the same as engaging directly in copyright infringement. So even though Oppenheim sees that no technology is going to stop them from finding infringers, he doesn't feel it's even an issue.
Clarke begs to differ by stating, using one of Oppenheim's analogies, "Manufacturers of a mask used in a bank robbery are certainly not responsible for the criminal behavior of the bank robbers."
The whole debate is very interesting reading. Definitely worth checking out!