Cuban missile crisis

The Cuban missile crisis was a stand-off in 1962 between the USA and USSR over the siting of Russian nuclear missiles in Cuba, which would have placed them in close range to mainland USA (like the US ones in Europe were to Russia). The world got close to nuclear war, an outcome that was worst for everyone, but for each side they could lose if they backed down first. It can be seen as a real-life version of the prisoners' dilemma, except that happily the US and USSR leadership could talk to one another and find a way to resolve the conflict. For AI this illustrates the importance of agent communication.