We know of nearly 70 military nuclear accidents since 1950. These include several incidents of lost or missing nuclear weapons. Many incidents have involved explosions and/or fires or some other mechanism for spreading fissile material. There were also a number of times when a nuclear war was narrowly averted. There are undoubtedly many more we do not (and may never) know about.
Click left to see examples of these dangerous accidents.
How long can our luck hold out?