Fifty years ago, on October 29, 1969, the internet was—in some sense—born. That’s the day that researchers sent the first message through the ARPANET (Advanced Research Projects Agency NETwork), which consisted of four computers in different locations. The message in question? “LO.” It was supposed to be “LOGIN,” but the network crashed after the first two letters.

Back in 1998, the historian Roy Rosenzweig began assembling a comprehensive early history of the internet, drawing from existing books. Rosenzweig writes that the internet was, undeniably, a product of the Cold War. In 1950, the federal government—which is to say, its military agencies—provided 75 to 80 percent of the money for computer development. “The American hegemony in computer markets—routinely attributed to American free markets—rests on a solid base of government-subsidized military funding,” Rosenzweig writes.

The military was eager to put computers to use in war, as demonstrated in U.S. Air Force Operation Igloo White, which, from 1967 to 1972, cost the government almost a billion dollars a year. The Air Force scattered sensors “shaped like twigs, jungle plants, and animal droppings” along the Ho Chi Minh Trail. The sensors were capable of picking up truck noise, body heat, and the scent of human urine and displaying this data on monitors in Thailand. These computers directed Phantom F-4 jet pilots to active areas and remotely controlled the release of bombs.

“It was the perfect fantasy of the closed world of computerized and centralized command and control,” Rosenzweig writes. But it didn’t really work. The Vietcong “fooled the sensors with taped truck noise and bags of urine, which duly provoked massive air strikes on empty jungle corridors.” That didn’t stop the Air Force from claiming success. The result, as a 1971 Senate report discovered, was that the number of “truck kills claimed by the Air Force [in Igloo White] last year greatly exceeds the number of trucks believed by the Embassy to be in all of North Vietnam.”

However farcical some of the federal government’s forays into computer technology may have been, the sheer willingness of the Defense Department to throw money at computer technology led to enormous progress. One goal of the defense establishment was to create a decentralized communications network that would let authorities communicate even if many of its nodes were destroyed in a nuclear war. This led Rand engineer Paul Baran to an insight that became key to the internet: the idea of breaking up messages into “packets” that could be sent individually and reassembled at a remote computer, making efficient use of communications lines.

In the early 1970s, not long after that first “LO” had traversed the early net, ARPA launched the “Internetting Project,” designed to link the ARPANET with satellite and radio networks using a common language. The eventual result was a new kind of packet-switching that came to be known as Transmission Control Protocol/Internet Protocol, or TCP/IP—an open standard still in use today.