On the first day of September in 1983, the Soviet Union shot down a plane. Its military officers thought it was a spy plane, they said later. But it was not: It was a passenger jet, Korean Air Lines Flight 007, and the 269 people on the plane all died.

The flight had originated in New York; one of the passengers was a U.S. congressman. At first, the Soviet Union wouldn't even admit its military had shot the plane down, but the Reagan administration immediately started pushing to establish what had happened and stymie the operations of the Soviet Aeroflot airline. President Reagan also made a choice that, while reported at the time, was not the biggest news to come out of this event: He decided to speed up the timeline for civilian use of GPS.

The U.S. had already launched into orbit almost a dozen satellites that could help locate its military craft, on land, in the air, or on the sea. But the use of the system was restricted. (It was meant, for instance, to help powerful weapons hit their targets—it wasn't the sort of tool governments usually want to make publicly available.) Now, Reagan said, as soon as the next iteration of the GPS system was working, it would be available for free.