Last week, former Soviet air defence commander Stanislav Petrov was awarded the Dresden Prize for preventing a nuclear war. Back in 1983, he determined that warnings of an incoming US nuclear missile strike were a false alarm as a result of a 'rare alignment of sunlight on high-altitude clouds and the satellites' designed to detect such launches.

The History Channel documentary below implies that, had Petrov passed on the warning, it would have triggered a Soviet counter-strike, though of course that would have been a decision for Soviet leaders, who presumably would have based their decision on more than a single source. Then again, those leaders would have assumed that they had only minutes to make a decision before possible annihilation.

Altogether, it's a pretty powerful argument for the abolition of nuclear weapons. Nuclear deterrence has prevented war between the great powers, but at the risk that perhaps a single human error could have catastrophic consequences.