But what would you do? You’re alone in a bunker, and alarms are screaming, and lights are flashing, and you have your training, and you have your intuition, and you have two choices: follow protocol or trust your gut. Either way, the world is counting on you to make the right call.

Petrov trusted himself. He reported the satellite's detection to his superiors—but, crucially, as a false alarm. And then, as Wired puts it, “he hoped to hell he was right.”

He was, of course. The U.S. had not attacked the Soviets. It was a false alarm. One that, had it not been treated as such, may have prompted a retaliatory nuclear attack on the U.S. and its NATO allies. Which would have then prompted … well, you can guess what it would have prompted.

As Petrov, now retired and living in a town near Moscow, puts it of his decision: “That was my job. But they were lucky it was me on shift that night.”

Thirty years later, there are lingering questions about the specific events of September 26, 1983. Was it really up to Petrov, the single man, to make the call? Weren't there other failsafes that would allow for malfunctioning technology? Wouldn't other cool heads, finally, have prevailed? Petrov, for his part, emphasizes the ambiguity of the situation, saying after the incident that he was never convinced the alarm was erroneous. (The odds of his getting it right, he now figures, were pretty much 50-50.)

One thing that seems clear, however, is that the world carried on into September 27, 1983 in some part because Stanislav Petrov decided to trust himself over malfunctioning machines. And that may have made, in a very broad and cosmic sense, all the difference. Petrov's colleagues were professional soldiers with purely military training; they would, being trained to follow instructions at all costs, likely have reported a missile strike had they been on shift at the time. Petrov, on the other hand, trusted his own intelligence, his own instincts, his own gut. He made the brave decision to do nothing.

And we’re here to read about him because of it.

Hat tip Nicholas Slayton and Chris Heller.

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