What's Mutual Assured Destruction?

A Minuteman nuclear missile in its silo at Warren Air Force Base in Wyoming, 1965.
Lowell Georgia/National Geographic/Getty Images

One can make the argument that the Cold War was nothing, if not a decades-long threat of complete and total nuclear annihilation. During this diplomatic and strategic conflict between the Union of Soviet Socialist Republics (USSR) and the United States, both sides engaged in massive nuclear proliferation (the stockpiling of nuclear weapons). Europe became a Cold War battleground, with nuclear missile silos located on both sides of the Iron Curtain. There was global tension over the very real possibility of death by nuclear bomb.

Despite concern over the hair trigger that the U.S. or the USSR (or both) might possess, when it came down to it, neither side went through with launching their missiles. This was proven on a few particularly gut-wrenching occasions. One was the Cuban Missile Crisis of October 1962. After learning that the Soviets were adding missiles to their increasing military presence in Cuba (just 90 miles off the coast of Florida), President Kennedy threatened a strike against the USSR if the missiles weren’t removed. After two tense weeks, the USSR relented [source: Global Security].


Another close call came during the Carter administration. At about 2:30 a.m. on June 3, 1980, security monitors at the North American Air Defense Command (NORAD) showed that the USSR had launched 2,220 nuclear missiles, headed toward America [source: Gates]. Within the 7-minute window afforded by a Soviet strike in the 1970s, National Security Director Zbigniew Brzezinski was on the verge of waking President Carter when he was told the attack was a false alarm.

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This wasn't the only false alarm during the Cold War that led the U.S. to believe that America was under attack. But in none of these instances did the U.S. pull the trigger and launch a nuclear strike. Why? The answer is found, in large part, in the doctrine of Mutual Assured Destruction (MAD). What is MAD, and how did it keep the Cold War belligerents from attacking one another? Find out on the next page.



The Nuclear Doctrine of MAD

The mushroom cloud from the atomic bomb dropped on Hiroshima, Japan, by the United States on Aug. 6, 1945.
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When the atom was split, a Pandora's box was opened. This scientific advancement led to the development of the atomic bomb -- humankind had never before possessed such a destructive weapon. The United States was the first to successfully develop the atomic bomb and the first to show the bomb's level of devastation when it unleashed two on Nagasaki and Hiroshima, Japan. Other nations scrambled to catch up; in the hands of just one country, this technology could arguably give that country control over the rest of the world.

Within eight years, the USSR had its own nuclear weapon -- the hydrogen bomb [source: Murray]. The ideological conflict between capitalism and communism sustained tensions between the U.S. and the USSR, and this prolonged conflict between the nations became known as the Cold War. From 1947 to 1991, the nations built up their nuclear arms, each expanding its arsenal in pace with the other. It was soon clear that both sides had built and stockpiled enough nuclear warheads that the U.S. and USSR could wipe out each other (and the rest of the world) several times over. They had reached nuclear parity, or a state of equally destructive capabilities.


As a result, the nuclear strategy doctrine of Mutual Assured Destruction (MAD) emerged in the mid-1960s. This doctrine was based upon the size of the countries' respective nuclear arsenals and their unwillingness to destroy civilization. MAD was unique at the time. Never before had two warring nations held the potential to erase humanity with the entry of a few computer codes and the turn of matching keys. Ironically, it was this powerful potential that guaranteed the world's safety: Nuclear capability was a deterrent against nuclear war.

Because the U.S. and the USSR both had enough nuclear missiles to clear each other from the map, neither side could strike first. A first strike guaranteed a retaliatory counterstrike from the other side. So launching an attack would be tantamount to suicide -- the first striking nation could be certain that its people would be annihilated, too.

The doctrine of MAD guided both sides toward deterrence of nuclear war. It could never be allowed to break out between the two nations. And it virtually guaranteed no conventional war would, either. Eventually, conventional tactics -- like non-nuclear missiles, tanks and troops -- would run out, and the inevitable conclusion of a nuclear strike would be reached. Since that end was deemed unacceptable by the Soviets and Americans, there was no chance of an engagement that could lead to this conclusion.

But MAD didn’t exactly create an atmosphere in which Soviet premiers and American presidents felt like they could shake hands and call the whole thing off. The nations had very little trust in each other -- and with good reason. Each side was steadily building its nuclear arsenal to remain an equal party in the MAD doctrine. A détente, or uneasy truce, developed between the U.S. and USSR. They were like two gunslinging foes, adrift alone in a life boat, each armed and unwilling to sleep.

So the situation had to be managed. On the next page, find out how nuclear proliferation was controlled.


Management of Nuclear Proliferation under the MAD Doctrine

Secretary of Defense Robert McNamara in 1967
Stan Wayman/Time Life Pictures/Getty Images

There are two defining characteristics of the doctrine of Mutual Assured Destruction. One, each side must have the nuclear capability to wipe out the other. And two, each side must be convinced the other has the nerve to launch a nuclear strike. In a speech in 1967, Defense Secretary Robert McNamara described how the U.S. achieved nuclear deterrence through MAD: “We do this by maintaining a highly reliable ability to inflict unacceptable damage upon any single aggressor or combination of aggressors at any time during the course of a strategic nuclear exchange, even after absorbing a surprise first strike” [source: McNamara].

Over time, nuclear delivery became more refined and the nightmare of an all-out nuclear holocaust less realistic. Both the U.S. and USSR invested heavily in technology that directed thermonuclear weapons from mindless, clobbering bombs to precise surgical instruments. Missile guidance systems allowed for more exact strikes, and the placement of missiles around the globe -- from allied nations to submarines cruising the world’s oceans -- created a virtual nuclear minefield. All-out annihilation was replaced by other options for a nuclear strike [source: Battilega].


People began analyzing ways that nuclear war could play out. One theory is called ladder of escalation. Under this strategy, one side launches a first strike, followed by a counterstrike from the other side. This exchange continues like a chess game, with each side increasing the level of destruction with each successive strike. For example, targeting civilian populations comes after strikes against military targets [source: Croddy, et al]. Each strike gives the other the option to back down or return fire. It’s kind of like trading punches with another person; each punch becomes increasingly powerful. The idea is to step up the force little by little until one heavy blow turns out to be the final punch as the weakened opponent backs down. All-out nuclear war, by contrast, is more akin to two parties shooting each other point-blank in the head.

Fans of the 1983 movie "War Games" will recognize this kind of strategy. In the film, a renegade supercomputer, capable of launching an American first strike, mulls over the best way to win a nuclear war. The computer runs through scenarios like a set of infinite games, considering a strike launched from Europe or from nuclear subs, and other endless possibilities. The computer finds there’s no way to win: Each first strike results in a counterstrike and both sides lose.

Mutual Assured Destruction really does have a basis in games. The same underlying mathematic principles that dictate maneuvers in games like Scrabble and Monopoly were used to examine nuclear strategy during the Cold War in a discipline called game theory. The doctrine of MAD, specifically, shares its basis with a game theory experiment called the prisoner’s dilemma.

In this scenario, two criminals are apprehended by police and questioned separately. The dilemma comes from each criminal's uncertainty as to what his cohort will do. If one confesses, the other is released but the confessor is punished. If one criminal implicates the other, the rat will be freed but the other person punished. The best course of action in this scenario (or in nuclear war) is inaction. By remaining mute (or unwilling to launch a first strike), neither party can be implicated (or destroyed).

It’s the same things that the computer Joshua learns in "War Games:" The only way to win in nuclear war is not to play.

For more information on the Cold War and other related topics, visit the next page.


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