Questions: Arms Race Dynamics and Stability

Question 1

State A develops highly accurate ballistic missiles capable of destroying State B's nuclear missiles while they are still in their silos. How does this most likely affect strategic stability?

• A. It increases stability by demonstrating military superiority and deterring any attack
• B. It is neutral — accuracy matters only for conventional weapons, not nuclear deterrence
• C. It destabilizes deterrence by giving State B a 'use them or lose them' incentive to strike first in a crisis
• D. It stabilizes deterrence by reducing the total explosive yield of nuclear exchanges

Answer: (C)

Highly accurate counterforce weapons threaten the adversary's retaliatory capacity — if State A can destroy State B's missiles on the ground, State B faces a dangerous logic in a crisis: strike first before they're disarmed, or wait and risk losing all capability. This first-strike incentive is exactly what makes counterforce weapons destabilizing. Stability requires that both sides maintain confidence in their ability to retaliate even after absorbing a first strike (second-strike capability). Counterforce weapons undermine this confidence.

Question 2

In the Richardson model of arms races, what condition produces an unstable (runaway) arms buildup?

• A. When both states have equal military capabilities
• B. When the product of the two states' reaction coefficients exceeds one
• C. When one state has a significant first-strike capability
• D. When grievance levels are higher than fatigue costs on both sides

Answer: (B)

In Richardson's formal model, each state's rate of armament is proportional to the adversary's current level minus a fatigue term. The system's equilibrium is unstable when the product of the two reaction coefficients (how strongly each state responds to the other's buildup) exceeds one — meaning mutual overreaction creates a positive feedback loop spiraling without bound. This mathematical insight identifies the key policy lever: reducing how strongly either side reacts to the other's buildup can stabilize an arms race even without reducing absolute levels.

Question 3

A state that maintains a secure second-strike capability — a surviving arsenal sufficient for devastating retaliation — has less incentive to strike first, even during a severe crisis.

• T. True
• F. False

Answer: True

Second-strike capability is the foundation of stable deterrence. If a state is confident it can absorb a first strike and still retaliate decisively, it has no incentive to strike preemptively — even under pressure. The first strike is pointless if it cannot prevent devastating retaliation. This is the logic of mutually assured destruction (MAD): stability emerges not from the absence of weapons but from a configuration where first strikes are irrational for both sides.

Question 4

Missile defense systems are stabilizing because they protect civilian populations from nuclear attack, reducing the incentive to strike first.

• T. True
• F. False

Answer: False

This is a persistent intuition that strategic analysis consistently overturns. Missile defenses threaten the adversary's second-strike confidence: if State A's defenses can intercept State B's retaliatory missiles, State B's deterrent loses credibility. This gives State B an incentive to expand its offensive arsenal or to 'use missiles before defenses are deployed.' Rather than stabilizing deterrence, missile defenses can trigger arms races and undermine the mutual second-strike confidence that makes deterrence stable. This is why arms control treaties like the ABM Treaty explicitly limited missile defenses.

Question 5

Explain why counterforce weapons are destabilizing while countervalue weapons combined with secure second-strike arsenals tend to be stabilizing.

Model answer: Counterforce weapons can destroy the adversary's military forces before they are used, threatening their second-strike capability. This creates a 'use them or lose them' logic in a crisis: both sides face incentives to strike first rather than wait to be disarmed. Each side's restraint becomes a gamble that the other won't exploit. Countervalue weapons, by contrast, can destroy cities but cannot reliably disarm the adversary — so even after a first strike, massive retaliation remains possible. When both sides have secure retaliatory capacity, first strikes are irrational: no achievable gain justifies the guaranteed devastating response. The stability comes not from the absence of armaments but from the mutual impossibility of a rational first strike.

Arms control agreements like SALT and START targeted counterforce capabilities specifically — constraining accuracy, warhead numbers, and delivery systems that could threaten retaliatory arsenals — precisely to preserve the second-strike confidence that stabilizes deterrence.