A situation in which one does, or already has done, what redarmy11 tells you to do or already has telled.
Diktats are usually issued in times of great uncertainty when society has vital but impossibly complex decisions to make about its future path. Though the Hammer, when it falls, usually brings with it great pain, anguish, bloodshed and loss of life, a surprisingly large percentage of the populace will eventually be found to agree with the Official History of the time, which will deem the Diktat to have been Necessary and For the Greater Good.
Diktats usually bring a satisfying finality to all the worrying and the belly-aching and the procrastinating, and mark the moment when all voices are silenced, and humanity is thrust roughly and reluctantly into a cold, frightening and impersonal new era.
A blood stained wall