When Edward J. Snowden, the disaffected National Security Agency contract employee, purloined tens of thousands of classified documents from computers around the world, his actions — and their still-reverberating consequences —

When Edward J. Snowden, the disaffected National Security Agency contract employee, purloined tens of thousands of classified documents from computers around the world, his actions — and their still-reverberating consequences — heightened international pressure to control the network that has increasingly become the world’s stage. At issue is the technical principle that is the basis for the Internet, its “any-to-any” connectivity. That capability has defined the technology ever since Vinton Cerf and Robert Kahn sequestered themselves in the conference room of a Palo Alto, Calif., hotel in 1973, with the task of interconnecting computer networks for an elite group of scientists, engineers and military personnel. The two men wound up developing a simple and universal set of rules for exchanging digital information — the conventions of the modern Internet. Despite many technological changes, their work prevails. But while the Internet’s global capability to connect anyone with a...