signs of non-violence
The Campaign for Nuclear Disarmament symbol was designed by Gerald Holtom for the Aldermaston March at Easter, 1958. It is composed of two semaphore letters, N and D, for nuclear disarmament.
Semaphore, the signalling with flags, was used in both WWI and WWII and is still taught in the Navy. For distances under 2 miles and in daylight it is faster, evidently, than flashing lights which can be more easily intercepted. The hand-held flags developed from the semaphore tower, an invention of Robert Hooke in 1684 to send messages through a series of such towers: 150 miles in two minutes according to The Flag Press.
Holtom had been a conscientious objector during WWII, so his experience of semaphoring was not learned in the Navy, but it was a familiar enough system of signs still that the N and the D, held in a circle for earth had currency. The N and D diagram above clearly shows a boy scout demonstrating the alphabet.
We know now that nuclear disarmament does not necessarily mean peace, it means ongoing dirty ground wars with increasingly high civilian collateral damage. The symbol was used during the Civil Rights movement and came to be associated with non-violence, and then by the anti-Vietnam War movement. Its now general linkage to peace has dropped all the particulars, and if there was ever a word that has become discredited by overuse and over-application it is the word peace.
The transportability of this symbol, literally as buttons, but also easily drawn, applicable to almost any kind of protest movement including the anti-abortion lobby, and its affiliation to unconventional life styles has rendered it near meaningless other than its core message that still semaphores non-violence. This must be what has given it such a long life.