It was done on a Saturday night dare made at a local bar. It was done to stop the missile from launching itself. It was part of a demonstration for the Strategic Defence Initiative. In the early 1980's in New York State, a local farmer rammed the door of an Atlas silo with a truck. Before the early US strategic missiles were equipped with electronic locks, permissive action links or PALs, they had security devices known as ESDs.
News arrives that the war is over.
There is no way at all to stop the launch. Then PAL-like electronic locks were installed, that blocked a launch unless the crew received the unlocking code from higher up. The change was not motivated by worries about the reliability of the launch crews. Carried by a military aide, it is said to accompany the President at all times. The Vice-president also is normally assigned a football, but one declined it.