Presidential Joke Day is observed on August 11, 2018. On August 11, 1984, United States President Ronald Reagan, while running for re-election, was preparing to make his weekly Saturday address on National Public Radio. As a sound check prior to the address, Reagan made the following joke to the radio technicians: "My fellow Americans, I'm pleased to tell you today that I've signed legislation that will outlaw Russia forever. We begin bombing in five minutes."
Contrary to popular misconception, this microphone gaffe was not broadcast over the air, but rather leaked later to the general populace. Though this was not the first time Reagan had joked prior to giving a speech or address, the Soviet official news agency, TASS, condemned the joke, declaring that "The USSR condemns this unprecedented and hostile attack by the US President" and that "this kind of behavior is incompatible with the great responsibility borne by heads of nuclear states for the destinies of their own people and mankind".
The quip became the basis for a song titled "Five Minutes," as well as "A is for Atom (B is for Bomb)" by Monte Cazazza's band The Atom Smashers, both of which began with a clip of the recording. (With material from: Wikipedia)