Only two nuclear weapons have been used since nuclear weapons were developed,

And I have the impression that relatively low-ranking people helped produce this outcome by keeping information from their superiors. Petrov chose not to report a malfunction of the early warning system until he could prove it was a malfunction. People during the Korean war and possibly Vietnam seem not to have passed on the fact that pilots from Russia or America were cursing in their native languages over the radio (and the other side was hearing them).

This in fact is part of why I don't think we 'survived' through the anthropic principle. Someone born after the end of the Cold War could look back at the apparent causes of our survival. And rather than seeing random events, or no causes at all, they would see a pattern that someone might have predicted beforehand, given more information.

This pattern seems vanishingly unlikely to save us from unFriendly AI. It would take, at the very least, a much more effective education/propaganda campaign.