Jacobo Prisco at CNN returns to 1958, when a new symbol appeared at protests against nuclear weapons in the UK.
"It's a minor masterpiece with major evocative power," said design guru and cultural critic, Stephen Bayley, in an email. "It speaks very clearly of an era and a sensibility.
"It is, simply, a fine period piece: the ordinary thing done extraordinarily well."
The design is meant to represent the letters "N" and "D" — standing for "nuclear disarmament" — as they appear in the semaphore alphabet, which is used by sailors to communicate from a distance with flags.
Gerald Holtom designed it,