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A decade-plus of anthropological fieldwork among hackers and like-minded geeks has led me to the firm conviction that these people are building one of the most vibrant civil liberties movements we’ve ever seen. It is a culture committed to freeing information, insisting on privacy, and fighting censorship, which in turn propels wide-ranging political activity. In the last year alone, hackers have been behind some of the most powerful political currents out there. Before I elaborate, a brief word on the term “hacker” is probably in order. Even among hackers, it provokes debate. For instance, on the technical front, a hacker might program, administer a network, or tinker with hardware. Ethically and politically, the variability is just as prominent. Some hackers are...