The most important computer you’ve never heard of

It’s not unusual to hear that a particular military technology has found its way into other applications, which then revolutionized our lives. From the imaging sensors that were refined to fly on spy satellites to advanced aerodynamics used on every modern jetliner, many of these ideas initially sounded like bad science fiction.

So did this one.

SAGE, the Semi-Automatic Ground Environment, was the solution to the problem of defending North America from Soviet bombers during the Cold War. Air defense was largely ignored after World War II, as post-war demilitarization gave way to the explosion of the consumer economy. The test of the first Soviet atomic bomb changed that sense of complacency, and the US felt a new urgency to implement a centralized defense strategy. The expected attack scenario was waves of fast-moving bombers, but in the early 1950’s, air defense was regionally fragmented and lacked a central coordinating authority. Countless studies tried to come up with a solution, but the technology of the time simply wasn’t able to meet expectations.