I use the words "unauthorized behavior" rather than "accident" because we must guard against many types of events— psychopathic or irrational individ… - Herman Kahn

The unacceptability of the Doomsday Machine raises awkward, unpleasant, and complicated questions that must be considered by both policy maker and technician. If it is not acceptable to risk the lives of the three billion inhabitants of the earth in order to protect ourselves from surprise attack, then how many people would we be willing to risk? I believe that both the United States and NATO would reluctantly be willing to envisage the possibility of one or two hundred million people (i.e., about five times more than World War II deaths) dying from the immediate effects, even if one does not include deferred long-term effects due to radiation, if an all-out thermonuclear war results from a failure of Type I Deterrence. With somewhat more controversy, similar numbers would apply to Type II Deterrence. (For example, some experts would concede the statement for an all-out Soviet nuclear attack on Europe, but not if the Soviets restricted themselves to the use of conventional weapons.) We are willing to live with the possibility partly because we think of it as a remote possibility. We do not expect either kind of deterrence to fail, and we do not expect the results to be that cataclysmic if deterrence does fail.

In addition to the obvious dangers, there is another subtle but by no means minor disadvantage to a pure deterrence posture: the threat of mutual suicide is a very uninspiring concept, no matter how logical it may seem. If it happened to involve explicitly the annihilation of all humanity it would also be totally immoral; one doubts if it could long remain an important part of United States policy.

Here is another form of deterrence which, while not a Doomsday Machine, is still an"ultimate" of a sort. This could be called the Homicide Pact Machine, an attempt to make a failure of Type I Deterrence mean automatic mutual homicide. The adherents to this somewhat more practical device hope to divide the work of deterrence in a natural way: We destroy the enemy and the enemy destroys us, neither of us cheating by buying any effective Counterforce as Insurance for our respective societies. The Homicide Pact Machine is clearly more satisfactory to both humanitarians and neutrals than the Doomsday Machine and both should make the distinction.