Within every culture, there is a public domain—a lawyer-free zone, unregulated by the rules of copyright. Throughout history, this part of culture has been vital to the spread and development of creative work. It is the part that gets cultivated without the permission of anyone else.

This public domain has always lived alongside a private domain—the part of culture that is owned and regulated, that part whose use requires the permission of someone else. Through the market incentives it creates, the private domain has also produced extraordinary cultural wealth throughout the world. It is essential to how cultures develop.

Traditionally, the law has kept these two domains in balance. The term of copyright was relatively short, and its reach was essentially commercial. But a fundamental change in the scope and nature of copyright law, inspired by a radical change in technology, now threatens this balance. Digital technologies have made it easy—indeed, too easy—for creative work in the private domain to spread without permission. Piracy is rampant on the highways of digital technology. In response, code writers (both legislators and technologists) have created an unprecedented array of weapons (both legal and technical) to wage war on the pirates and restore control to the owners of culture. Yet the control these weapons will produce is far greater than anything we have seen in our past.

So, for example, the United States has radically increased the reach of copyright regulation. And through the World Intellectual Property Organization, wealthy countries everywhere are pushing to impose even tighter restrictions on the rest of the world. These legal measures will soon be supplemented by extraordinary technologies that will secure to the owners of culture almost perfect...