minuteman (n.)

also minute-man, in U.S. history, one of a class of militia who held themselves in readiness for immediate service in arms (i.e. ready "at a minute's notice" or "in a matter of minutes"), 1774, from minute (n.) + man (n.). As the name of a type of ICBM, from 1961, so called because they could be launched with very little preparation.