peace symbol
This tag should be used when a picture contains the circular symbol: ☮ which is commonly known as the "Peace Symbol" but specifically as the CND logo (Campaign for Nuclear Disarmament), being actually made up of the semaphore symbols for N and D.
Originally designed for the British nuclear disarmament movement by Gerald Holtom in 1958, it took on a more generic association with peace in general after being made into badges that were sold in the millions on American campuses.
For the hand sign with the index and middle fingers raised, see V.