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Mutually assured destruction

Mutually assured destruction is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Mutually assured destruction rather than just read about it. In short: Mutually assured destruction or mutual assured destruction (MAD) is a doctrine of military strategy and national security policy which posits that a full-scale use of nuclear weapons by an attacker on a nuclear-armed defender with second-strike capabilities would result in the complete annihilation of both the attacker and the defender. It is based on the theory of rational deterrence, which holds that the threat of…

Mutually assured destruction — main illustration
Mutually assured destruction — illustration

Key takeaways

  • Mutually assured destruction belongs to physics; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Mutually assured destruction to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Mutually assured destruction from memory before moving on to harder problems.

Reference excerpt

Mutually assured destruction or mutual assured destruction (MAD) is a doctrine of military strategy and national security policy which posits that a full-scale use of nuclear weapons by an attacker on a nuclear-armed defender with second-strike capabilities would result in the complete annihilation of both the attacker and the defender. It is based on the theory of rational deterrence, which holds that the threat of using strong weapons against the enemy prevents the enemy's use of those same weapons. The strategy is a form of Nash equilibrium in which, once armed, neither side has any incentive to initiate a conflict or to disarm. The result may be a nuclear peace, in which the presence of nuclear weapons decreases the risk of crisis escalation, since parties will seek to avoid situations that could lead to the use of nuclear weapons. Proponents of nuclear peace theory therefore believe that controlled nuclear proliferation may be beneficial for global stability. Critics argue that nuclear proliferation increases the chance of nuclear war through either deliberate or inadvertent use of nuclear weapons, as well as the likelihood of nuclear material falling into the hands of violent non-state actors. The term "mutually assured destruction", commonly abbreviated "MAD", was coined by Donald Brennan, a strategist working in Herman Kahn's Hudson Institute in 1962. Brennan conceived the acronym cynically, spelling out the English word "mad" to argue that holding weapons capable of destroying society was irrational.

Theory

Under MAD, each side has enough nuclear weaponry to destroy the other side. Either side, if attacked for any reason by the other, would retaliate with equal or greater force. The expected result is an immediate, irreversible escalation of hostilities resulting in both combatants' mutual, total, and assured destruction. The doctrine requires that neither side construct shelters on a massive scale. If one side constructed a similar system of shelters, it would violate the MAD doctrine and destabilize the situation, because it would have less to fear from a second strike. The same principle is invoked against missile defense. The doctrine further assumes that neither side will dare to launch a first strike because the other side would launch on warning (also called fail-deadly) or with surviving forces (a second strike), resulting in unacceptable losses for both parties. The payoff of the MAD doctrine was and still is expected to be a tense but stable global peace. However, many have argued that mutually assured destruction is unable to deter conventional war that could later escalate. Emerging domains of cyber-espionage, proxy-state conflict, and high-speed missiles threaten to circumvent MAD as a deterrent strategy. The primary application of this doctrine started during the Cold War (1940s to 1991), in which MAD was seen as helping to prevent any direct full-scale conflicts between the United States and the Soviet Union while they engaged in smaller proxy wars around the world. MAD was also responsible for the arms race, as both nations struggled to keep nuclear parity, or at least retain second-strike capability. Although the Cold War ended in the early 1990s, the MAD doctrine continues to be applied. Proponents of MAD as part of the US and USSR strategic doctrine believed that nuclear war could best be prevented if neither side could expect to survive a full-scale nuclear exchange as a functioning state. Since the credibility of the threat is critical to such assurance, each side had to invest substantial capital in their nuclear arsenals even if they were not intended for use. In addition, neither side could be expected or allowed to adequately defend itself against the other's nuclear missiles. This led both to the hardening and diversification of nuclear delivery systems (such as nuclear missile silos, ballistic missile submarines, and nuclear bombers kept at fail-safe points) and to the Anti-Ballistic Missile Treaty. This MAD scenario is often referred to as rational nuclear deterrence. When the possibility of nuclear warfare between the United States and Soviet Union started to become a reality, theorists began to think that mutually assured destruction would be sufficient to deter the other side from launching a nuclear weapon. Kenneth Waltz, an American political scientist, believed that nuclear forces were in fact useful, but even more useful in the fact that they deterred other nuclear threats from using them, based on mutually assured destruction. The theory of mutually assured destruction being a safe way to deter continued even farther with the thought that nuclear weapons intended on being used for the winning of a war, were impractical, and even considered too dangerous and risky. Even with the Cold War ending in 1991, deterrence from mutually assured destruction is still said to be the safest course to avoid nuclear warfare.

Effectiveness of the theory according to empirical studies A study published in the Journal of Conflict Resolution in 2009 quantitatively evaluated the nuclear peace hypothesis and found support for the existence of the stability-instability paradox. The study determined that nuclear weapons promote strategic stability and prevent large-scale wars but simultaneously allow for more low intensity conflicts. If a nuclear monopoly exists between two states, and one state has nuclear weapons and its opponent does not, there is a greater chance of war. In contrast, if there is mutual nuclear weapon ownership with both states possessing nuclear weapons, the odds of war drop precipitously.

History

Pre-1945

… excerpt ends here. Continue reading the full article.

Illustrations

Mutually assured destruction illustration
Mutually assured destruction illustration
Mutually assured destruction illustration
Mutually assured destruction illustration
Mutually assured destruction illustration

Worked examples

Example 1 — a first encounter with Mutually assured destruction

Start with the simplest possible case. Write down what Mutually assured destruction claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Mutually assured destruction before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Mutually assured destruction ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Mutually assured destruction

In research
Mutually assured destruction appears in physics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Mutually assured destruction in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Mutually assured destruction is common in secondary-school and first-year university syllabi. It links to neighbouring topics Cold War policies, Cold War terminology, English phrases, so understanding it makes those chapters shorter.
In everyday life
Look for Mutually assured destruction outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Mutually assured destruction in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Mutually assured destruction means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Mutually assured destruction out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Mutually assured destruction in simple terms?

Mutually assured destruction or mutual assured destruction (MAD) is a doctrine of military strategy and national security policy which posits that a full-scale use of nuclear weapons by an attacker on a nuclear-armed defender with second-strike capabilities would result in the complete annihilation…

Why does Mutually assured destruction matter?

Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Mutually assured destruction?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Mutually assured destruction.

Tags

  • Cold War policies
  • Cold War terminology
  • English phrases
  • Military doctrines
  • Nuclear doomsday
  • Nuclear strategy
  • Nuclear warfare
  • Nuclear weapons
  • Theories of history

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