Much has been made of the Internet’s ability to resist such control. The network’s technological origins, we are sometimes told, lie in the cold war–era quest for a communications infrastructure so robust that even a nuclear attack could not shut it down. Although that is only partly true, it conveys something of the strength inherent in the Internet’s elegantly decentralized design. With its multiple, redundant pathways between any two network nodes and its ability to accommodate new nodes on the fly, the TCP/IP protocol that defines the Internet should ensure that it can keep on carrying data no matter how many nodes are blocked and whether it’s an atom bomb or a repressive regime that does it. As digital-rights activist John Gilmore once famously said, “The Internet interprets censorship as damage and routes around it.”

That is what it was designed to do anyway. And yet if five phone calls can cut off the Internet access of 80 million Egyptians, things have not worked quite that way in practice. The Egyptian cutoff was only the starkest of a growing list of examples that demonstrate how susceptible the Internet can be to top-down control. During the Tunisian revolution the month before, authorities had taken a more targeted approach, blocking only some sites from the national Internet. In the Iranian postelection protests of 2009, Iran’s government slowed nationwide Internet traffic rather than stopping it altogether. And for years China’s “great firewall” has given the government the ability to block whatever sites it chooses. In Western democracies, consolidation of Internet service providers has put a shrinking number of corporate entities in control of growing shares of Internet traffic, giving companies such as Comcast and AT&T both the incentive and the power to speed traffic served by their own media partners at the expense of competitors.

Internet Freedom Fighters Build a Shadow Web: Scientific American. A typically fantastic article by Julian Dibbell.