MOD 14: Nuclear_Weapons_I_-_Tagged

Nuclear Weapons and U.S. Foreign Policy

I. Introduction: Nuclear Weapons and Post–1945 U.S. Strategy

A. Transformative Impact

• The introduction of nuclear weapons in 1945 fundamentally reshaped U.S. foreign policy and global security.

• Before 1945: U.S. national security centered on defense — building armies and fortifications.

• After 1945: The strategy shifted to deterrence — preventing war through the threat of nuclear retaliation.

B. Policy Shift

• Nuclear weapons made direct defense impossible (no defense against total destruction).

• The U.S. adopted a policy based on deterring aggression, particularly from the Soviet Union during the Cold War.

• Emphasis on credibility, control, and survivability of nuclear forces became central to foreign policy.

C. Core Problem

• The same weapons that guaranteed security also created new risks of miscalculation, accidents, or escalation, complicating national security management.

II. The Nuclear Revolution

A. Definition

• The nuclear revolution describes how nuclear weapons completely changed the nature of warfare and international politics.

• First true revolution in military affairs since the invention of gunpowder.

B. Key Differences from Conventional Weapons

1. Scale of Destruction – Nuclear weapons can annihilate entire cities in seconds.

2. Targeting Civilians – Primary focus shifts from enemy armies to population centers and infrastructure.

3. No Meaningful Victory – A nuclear war would destroy both sides; victory and defeat lose meaning.

C. Consequences

• War between great powers became unthinkable due to mutually assured destruction.

• The balance of terror created strategic stability, preventing direct superpower wars.

III. Deterrence Theory

A. Definition

• Deterrence: Preventing attack by threatening severe retaliation.

• It relies on fear, not the actual use of force.

B. Types of Deterrence

1. General Deterrence:

   • Long-term maintenance of nuclear readiness to prevent aggression.

2. Immediate Deterrence:

   • A specific threat issued in response to an imminent crisis.

C. Deterrence vs. Defense

D. Example

• The U.S. and Soviet Union deterred one another during the Cold War through the fear of mutual annihilation rather than by direct combat.

IV. Second-Strike Capability and Mutually Assured Destruction (MAD)

A. Second-Strike Capability

• The ability of a state to retaliate with nuclear weapons even after suffering a surprise attack.

• Ensures that no first strike can eliminate retaliation.

B. Mutually Assured Destruction (MAD)

• A condition where both sides have secure second-strike capabilities.

• Guarantees that any nuclear war will destroy both attacker and defender.

C. Relationship Between the Two

• MAD depends on second-strike capability.

  • If both sides can retaliate, neither has an incentive to start a war.

• Creates a stable balance of terror — deterrence through mutual vulnerability.

V. Why Nuclear Weapons Can Make War Less Likely

A. Paradox of Nuclear Peace

• The fear of total destruction discourages leaders from initiating war.

• Even intense rivalries (e.g., U.S.–USSR) stayed cold, not hot.

B. Cold War Application

• Both superpowers avoided direct military conflict because the cost of escalation was existential.

• Crises (like the Cuban Missile Crisis) demonstrated the logic of caution under nuclear deterrence.

VI. The Problem of Credibility in Nuclear Deterrence

A. The Credibility Dilemma

• For deterrence to work, an adversary must believe you will carry out your threats — even when doing so would be catastrophic.

• Using nuclear weapons is inherently irrational, which makes credible threats hard to sustain.

B. Why Credibility Matters

• If threats are unbelievable, deterrence collapses and the opponent may call your bluff.

• Maintaining credibility is essential for both national and extended deterrence.

VII. Extended Deterrence and Alliance Commitments

A. Definition

• Extended deterrence: Using nuclear threats to protect allies (e.g., NATO members, Japan, South Korea).

B. Credibility Problem Intensified

• Would the U.S. risk its own cities to defend another country?

• To reassure allies, the U.S. has stationed troops and weapons abroad — a strategy called forward deployment.

C. Strategic Importance

• Strengthens alliances and prevents nuclear proliferation among allies by convincing them they are protected.

VIII. Building and Demonstrating Credibility

A. Two Components of Credibility

1. Capabilities – Having sufficient and survivable nuclear forces.

2. Resolve – Demonstrating the will to use them if necessary.

B. Tools to Demonstrate Credibility

1. Brinkmanship: Deliberately escalating crises to show commitment.

2. Tripwire Forces: Deploying small, exposed military units that ensure automatic retaliation if attacked.

3. Threat That Leaves Something to Chance: Introducing uncertainty and risk to make threats believable.

4. Public Pronouncements (Democracies): Leaders make public commitments that are politically costly to break, strengthening credibility.

IX. National Missile Defense (NMD)

A. Definition

• Defensive systems designed to intercept and destroy incoming nuclear missiles.

B. Impact on Stability

• Potentially destabilizing:

  • Undermines an adversary’s confidence in its second-strike capability.

  • Encourages preemptive strikes before defenses improve.

• Balance:

  • Effective for protection against small threats (rogue states) but risky among nuclear peers.

X. Nuclear Proliferation

A. Definition

• The spread of nuclear weapons technology and materials to additional states or non-state actors.

B. Types

1. Horizontal Proliferation: Spread to new countries (e.g., North Korea, Iran).

2. Vertical Proliferation: Growth of existing nuclear arsenals.

C. Risks

• More actors mean more potential for accidents, miscommunication, or unauthorized use.

• Increases chances of regional instability and terrorism.

XI. Summary and Key Takeaways

1. Nuclear weapons shifted U.S. policy from defense to deterrence.

2. The nuclear revolution created a world where total war is suicidal, not strategic.

3. Deterrence theory relies on credible threats rather than military victories.

4. MAD and second-strike capability are the foundation of Cold War stability.

5. Credibility — not just capability — is the cornerstone of deterrence.

6. Extended deterrence complicates credibility but strengthens alliances.

7. Brinkmanship, tripwires, and public commitments are tools to signal resolve.

8. Missile defense and nuclear proliferation both challenge long-term stability.