One cheap switch saved US from nuclear ...

[isaiah40]

Apparently a B52 bomber broke up over North Carolina in 1961 and one of the nuclear bombs it carried - out of two - almost detonated, but one cheap switch did not go off, thereby saving the east coast from a nuclear devastation.

[Metsfanmax]

Who needs an intercontinental hotline to avert a nuclear crisis when a simple switch will do?