I remember reading this elsewhere and the russian official was quoted in the lines of "It felt wrong cause if you wanna launch nukes, you launch them by the hundreds".
Also if you want to do a sneak attack you don't start it with the weapon your opponent can most easily detect.
So, the control center hasn't been taken out by a cruise missile and the submarine pens are untouched and the bomber airfields check in as OK... it just doesn't make sense as a sneak attack vector. Maybe every sub launched cruise missile in the fleet failed to work; unlikely.
Something not declassified yet, but probably would clear up a lot of confusion, is if the detector code was fooled by sunlight on clouds or whatever, the trajectory solver likely came up with bizarre results like the ICBM launch site was the center of Lake Michigan or downtown Chicago or the trajectory of the other missile has a best fit predicted impact point of Ohio or Mexico City.
They have plenty of practice analyzing the huge horizontal velocity vector of normal spacecraft launches. A strange sunlight reflection would tend to have zero horizontal velocity; the opfor seems to be bombing its own missile sites by tossing the ICBM exactly straight up and down? That seems a little odd unless someone's trying to set off a false flag leading to a real attack.
I would think it would be good defensive coding strategy to have different teams write and deploy the detector code vs the trajectory analysis code, such that if one messes up it really doesn't matter.
> Petrov's decision was based partly on a guess, he recalled. He had been told many times that a nuclear attack would be massive – an onslaught designed to overwhelm Soviet defenses at a single stroke. But the monitors showed only five missiles. "When people start a war, they don't start it with only five missiles," he remembered thinking at the time. "You can do little damage with just five missiles."
