The "D" Word V: Tenants of "Deterrence Theory"
By the end of the 1960’s, the era of mutual assured destruction was widely believed to have arrived. Both sides having deployed thermonuclear bombs and Intercontinental Ballistic Missiles is what had done it.
Along the way, something called “deterrence theory” had emerged. The theory set out the requirements for “deterrence,” or to put it another way, what might lead to a “failure of deterrence.”
A “failure of deterrence” was what would lead to mutual destruction, it was thought. Possibly to the end of life on earth. Not everyone believed it would do that, but everyone knew a general nuclear war would be bad for us. All of us. Everywhere. Very bad.
An early contribution to deterrence theory was made by two books—On Thermonuclear War (1960) and Thinking about the Unthinkable (1962)—written by an employee of the RAND Corporation named Herman Kahn. These books weren’t about deterrence so much as about different ways of conducting a thermonuclear war should one happen.
A thermonuclear war would be one in which the largest yielding “strategic” weapons were used, the ones that were hundreds times more powerful than the bombs we’d dropped on Japan. Kahn later worked up a scheme of the steps in escalation from an ordinary war that would take us into a thermonuclear war. The first version had 16 steps. A later version had 44 steps. You could skip some of the steps, I’m sure, and might want to if you thought it would give you an advantage.
The last step he called a “spasm.”
Kahn maintained that it was better to think about the unthinkable than not to. He seems to have believed, then, that the unthinkable was thinkable after all. Which I’m sure is the case, if you do your thinking in a certain kind of way.
Kahn later wrote a paper that recognized that to deter a first-strike with nuclear weapons, it would be necessary to have a second-strike capability. That made sense. A first-strike with thermonuclear weapons would otherwise be likely to conclude matters.
Let’s now look at some of the tenants of the deterrence theory that emerged during the 60’s.
For deterrence to work, the theory said, there would be certain requirements:
1. You must have a means of inflicting significant harm if and when the action you fear and wish to deter by fear is performed. (This “harm” was sometimes called “punishment” or “costs,” though these are all different things, aren’t they? “Costs” can have “benefits.” “Harm” doesn’t.)
2. The harm must be believed by those you wish to deter to follow with a very high probability, ideally with certainty, if they perform the action you wish to deter.
3. Your means of inflicting the harm must be seen to be reliably available to you.
4. You must be seen to be willing to inflict the harm if they do what you want to keep them from doing.
5. Your means of inflicting the harm must appear to be something that can’t be defeated by a surprise first strike on the one hand or a war of attrition on the other.
If you have met these requirements, you will have what the theory calls a credible deterrent. A deterrent you can believe in. And, more important, one your opponent might believe in.
Sounds reasonable. Maybe even watertight. But let’s look a little more at these requirements.
Consider the first one: to have a means of inflicting “significant harm” (sometimes called “punishment” or “costs,” most often “costs.”) What is crucial here is that when it comes to deterrence, it matters not at all how significant the deterrer thinks the harm is. What matters is how significant the deteree thinks it is.
It doesn’t matter that the Fox fears the “briar patch,” or that the Fox thinks Br’er Rabbit fears it if, in fact, Br’er Rabbit doesn't. There can be serious mismatches1 here, and in the relations between nations there have been mismatches of this kind. Would-be deterrers have sometimes had no idea or deeply mistaken ideas of how their intended deterees have seen the significance of their “deterrent.” The United States misread the resolve and capabilities of North Vietnam. More recently, Russia would seem to have misread the resolve and capabilities of Ukraine and NATO countries.
Let’s bring it down to street level. How is a police officer to deter someone determined to commit what has come to be called “suicide by cop” by provoking the officer into shooting them? Well, you might think, by refusing to be provoked into shooting them. But what if the person is threatening to harm others?
If someone intends to commit suicide, you can’t deter them by threatening to kill them, that’s obvious. They don’t fear what you might fear, death. It turns out, however, that you may be able to deter them by threatening to kill them in some way other than the way they wish to die. Some people threatening to jump off buildings have been talked down by threatening to shoot them.
Isn’t that interesting? Even if it doesn’t matter to us that we die, it can matter to us how we die. How we die can be the harm we fear.
The capacity to inflict “significant” harm need not be real, but the one to be deterred must think it is or might be. Bluffs can work. Sometimes.
In any case, a deterrent will have no force unless the deteree knows about it.
In the movie Doctor Strangelove (1965), the Soviets have built a “Doomsday Machine” that will launch nuclear weapons automatically if the Soviets are attacked with nuclear weapons. Unfortunately, the Soviets haven’t gotten around to telling the U.S. President Merkin Muffley about it. Under those circumstances, their Doomsday Machine could have had no deterrent force.
In the movie, this wouldn’t have mattered since the attack about to happen on the Soviet Union has been ordered by the deranged General Ripper on the grounds that the Soviets have been polluting our “precious bodily fluids.” In the deluded, deranged General’s mind, the attack he has ordered is already a retaliation for an attack he has imagined, in his delusion, that we have already experienced. Deterrence also may not work when the deteree is deluded or deranged.
After the Soviets developed Intercontinental Ballistic Missiles in 1957, President Eisenhower, who was believed by us to be the only one who could authorize the use of our nuclear weapons, wanted to be sure the Soviet Union couldn’t prevent us from using our nuclear weapons to retaliate if they managed to kill President Eisenhower in a surprise attack. He secretly authorized certain military commanders in the field to order the use of nuclear weapons in what were called conditions of “grave necessity” if they weren’t able to reach him. What amounted to “grave necessity” was left to the commanders to decide.
Unfortunately, President Eisenhower didn’t tell anyone he had done this. Not us. Not the military leaders in the Pentagon. Not our allies. Not the Soviets.
Since no one knew about this “pre-delegation,” it couldn’t have acted as a deterrent. It could only have acted to assure that if we were attacked by the Soviet Union, not only the United States and millions of its inhabitants but also the Soviet Union and millions of its inhabitants would be destroyed.
And if we had conducted a nuclear attack on them because of a false alarm, it would be what, by mistake, caused a nuclear war.
Next: More Wrinkles in Deterrence Theory
See Robert Jervis, “Deterrence and Perception,” in Strategy and Nuclear Deterrence, Princeton UP, 1984. This collection is one of the best sources of deterrence theory I’ve found.