War, bargaining failures, and nuclear deterrence

what is war?

organized violence between political entities, interstate war is coded as 1k battle deaths per year in most datasets, causes of war is the central question in mainstream IR, and the classifications are levels of analysis, distant vs proximate causes

What is Defensive Realism?

• State interest = survival/security

• States seek enough power to stay safe, not domination

• Too much power can threaten others

• Leads to the security dilemma: states arm themselves for defense, but others see it as a threat → war can occur unintentionally

Example from slide:

• WWI trench warfare

• Countries increased military power to protect themselves, but this triggered arms races and conflict.

What is Offensive Realism?

• State interest = power maximization

• States try to become the most powerful actor in the system

• Expansion increases security

• Competition for dominance often leads to war

Example from slide:

• Nazi Germany expansion (1939–1942)

• Germany invaded and conquered other states to increase power and dominance.

compare defensive realism and offensive realism

Defensive Realism

• Goal: security/survival

• Avoid excessive expansion

• War comes from security dilemmas

• Example: WWI arms buildup and trench warfare

Offensive Realism

• Goal: maximize power

• Expansion is strategic

• War comes from power competition

• Example: Nazi Germany expanding across Europe is a political theory that explores the interests of states in terms of security versus power maximization, highlighting how each approach leads to different outcomes in international relations.

What is a Coordination Game?

• Both players prefer to cooperate and coordinate actions

• Best outcome occurs when both choose the same strategy

• Cooperation gives the highest payoff for both

Example from slide:

• 10,10 outcome

  • Both players cooperate → best result for both

What is a Mixed-Motive Game?

• Players have both shared and conflicting interests

• Cooperation gives benefits, but each player wants a better deal

• Leads to bargaining

Example from slide:

• 1,1 outcome = suboptimal outcome

• Players fail to cooperate fully → worse outcome than possible

Key idea:

• War can occur when bargaining fails

What is a Zero-Sum Game?

• One player’s gain = the other player’s loss

• Interests are completely opposed

• Cooperation is difficult

Example from slide:

• Outcomes like 2,2 vs 0,4 show competitive trade-offs

Key idea:

• Conflict is more likely because one side winning means the other loses

Why is war considered a suboptimal outcome in bargaining theory?

• War is costly for both sides

• Both states would prefer a negotiated bargain

  • War happens when bargaining breaks down (e.g., mistrust, miscalculation)

What is a Bargaining Range in bargaining theory?

• The range of outcomes both states would accept instead of going to war

• Exists when there is overlap between each state’s acceptable outcomes

• If a deal falls within this range, peaceful agreement is possible

What happens when there is no bargaining range?

• No overlap between states’ acceptable outcomes

• Neither state will accept the other’s minimum demands

• War is likely

What happens when there is a small bargaining range?

• Small overlap between acceptable outcomes

• A deal is possible but hard to reach

• War is moderately likely

What happens when there is a large bargaining range?

• Large overlap between acceptable outcomes

• Many possible deals both sides would accept

• War is unlikely

Why do states prefer a bargained settlement over war?

• War is costly and risky

• Both states usually prefer any acceptable bargain to fighting

• War happens when bargaining fails or no range exists

Why can incentives to misrepresent (bluffing) cause bargaining failures?

• States have incomplete information about each other’s preferences.

• They do not know the other side’s worst acceptable outcome.

• This creates incentives to misrepresent or bluff about their true limits.

• States may claim they cannot accept certain deals to gain better concessions.

Key idea:
Bluffing and uncertainty about true preferences can prevent agreements even when a mutually beneficial deal exists.

What are commitment problems in bargaining failures?

• Occur when states cannot make credible promises not to revise a deal later.

Causes:

• Anarchy (no authority to enforce agreements)

• Changing distribution of power over time

Ways to increase credibility:

• Strong signals (e.g., red lines, last offers)

• Third-party involvement (audience costs)

• Legal commitments

• Reputation from past behavior

Key idea:
If states cannot trust commitments, they may reject agreements even when cooperation is possible.

What is indivisibility as a cause of bargaining failure?

• Occurs when the disputed issue is an indivisible good (“all or nothing”).

• The good cannot easily be divided or shared between states.

Examples:

• Territory (mountain, small island)

• Sacred or symbolic sites (place of worship)

Key idea:

• If the good cannot be split, compromise becomes difficult, making conflict more likely.

Possible solution:

• Creative arrangements (shared control, compensation), since indivisibility is often socially constructed.

How do domestic groups (Liberalism / Marxism) influence foreign policy and war?

• Some domestic groups benefit from conflict and lobby governments to take action.

Key actors:

• Military-industrial complex – defense industries benefiting from military spending

• Economic interest groups – e.g., oil companies, United Fruit Company (Guatemala 1954)

• Ethnic interest groups – e.g., Cuban Americans and the Bay of Pigs (1961)

• General public

Key idea:
Foreign policy can reflect the interests of influential domestic groups, not just national security.

Note:
Influence depends on political institutions (lobbying rules, ruling party, electoral system).

What is the bureaucratic politics model of foreign policy?

• Developed by Graham Allison in The Essence of Decision (1971).

• The state is not a unitary actor.

• Foreign policy results from bargaining among government agencies.

Key features:

• Different ministries and agencies have their own interests.

• “Where you stand depends on where you sit.”

• Some agencies may be hawkish (prefers more aggressive or military action) , others dovish (prefers peaceful solutions, diplomacy, or restraint).

• Agencies also influence how policies are implemented.

Key idea:
Foreign policy outcomes are shaped by internal government competition and bargaining, not just a single national interest.

How do constructivism and critical theories explain war through propaganda and representations?

• Ideas, identities, and narratives shape international politics, not just material power.

• Propaganda constructs the enemy by portraying opponents as:

  • Evil, dangerous, or inhuman

  • A threat to national values or survival

• These representations shape public perception and identity (us vs. them).

• As a result, war becomes socially legitimized or justified.

Key idea:
War is influenced by how states represent and interpret others, not only by strategic interests or power.

what are individual level causes of war?

some individual characteristics of decision-makers make them more likely to accept the high costs of war, bounded rationality (People make decisions with limited information, limited time, and limited cognitive ability, so they choose a good enough option rather than the optimal one.),

and there are psychological factors and misperceptions: confirmation bias, updating priors, conveying information and intentions, overestimating hostility and intentionality, and groupthink

what is the diversionary theory of war?

• Leaders may start external conflicts to distract from domestic problems (economic crisis, low popularity, political instability).

• War can increase support through the “rally ’round the flag” effect, where citizens unite behind the leader during international conflict.

• Example: The Falklands War (1982) between Argentina and the UK.

• Evidence: Some cases support it, but overall evidence is mixed/inconclusive.

What are the strategic implications of nuclear weapons?

• Nuclear weapons have extremely high costs, making them different from conventional weapons.

• War between nuclear states risks Mutually Assured Destruction (MAD).

• States are in an “exchange of hostages” situation—each can destroy the other.

• Nuclear deterrence: the threat of nuclear retaliation helps prevent conflict.

What is second-strike capability in nuclear strategy?

• The ability of a state to retaliate with nuclear weapons even after being attacked first.

• Ensures that no country can eliminate the opponent’s nuclear forces completely.

Maintained through the nuclear triad:

• Land-based missiles (ICBMs)

• Strategic bombers

• Submarine-launched missiles (SLBMs)

Key idea:
Second-strike capability strengthens nuclear deterrence because a first strike would still trigger devastating retaliation.

Why are information and commitment important for nuclear deterrence?

• A state’s second-strike capability must be publicized so opponents know retaliation is possible.

• The state’s willingness to use nuclear weapons must be clear and credible.

Key idea:
Deterrence only works if the capability and the threat to use it are believable.

Why is rationality important for nuclear deterrence?

• Deterrence assumes leaders are rational actors.

• Rational leaders understand that using nuclear weapons would lead to catastrophic retaliation.

• Therefore, they avoid nuclear war to prevent mutual destruction.

Key idea:
Deterrence works only if leaders value survival and act rationally.

What is extended deterrence?

• When a nuclear state uses its nuclear weapons to deter attacks on its allies, not just itself.

• The state promises retaliation if an ally is attacked.

Example:
The U.S. nuclear umbrella protecting NATO allies, Japan, or South Korea.

Key idea:
Nuclear weapons extend protection beyond the state that owns them.

What is the stability–instability paradox?

• When nuclear deterrence makes large-scale war unlikely (stable).

• But this stability can encourage smaller conflicts or proxy wars (instability) because states believe escalation to nuclear war will be avoided.

Key idea:
Nuclear weapons reduce major wars but may increase smaller conflicts.

What is the vulnerability–invulnerability paradox?

• When a state feels invulnerable at the nuclear level (because nuclear war would be mutually destructive).

• But it may still be vulnerable to conventional attacks or smaller conflicts.

Key idea:
Nuclear weapons protect states from total war, but not from lower-level aggression.

Why does the dispersal of nuclear weapons increase risks?

• Nuclear weapons stored in multiple or remote locations can increase security risks.

Main risks:

1. Loss or accidents (misplacement, technical failures, mishandling)

2. Nuclear terrorism (weapons or materials stolen or accessed by non-state actors)

Key idea:
Dispersing nuclear weapons can improve survivability but increase security risks.

How does bureaucratic politics affect nuclear policy?

• Nuclear policy is shaped by a complex set of agencies, not a single rational decision-maker.

Risks:

1. Irrationality somewhere in the decision chain

2. Miscommunication (within government or between states)

3. Parochial interests (agencies promoting their own priorities)

Key idea:
Decisions about nuclear weapons can be influenced by internal bureaucratic competition and errors.

How might technological developments undermine nuclear deterrence?

• Improvements in accuracy and targeting increase the chances of successfully destroying an opponent’s nuclear weapons.

• This could threaten second-strike capability, which deterrence relies on.

• Low-yield nuclear weapons may make nuclear use seem more “limited” or usable.

Key idea:
New technologies may make nuclear war seem more feasible, weakening traditional deterrence based on mutual destruction.

How can we explain the non-use of nuclear weapons since 1945?

• Nuclear deterrence: fear of retaliation and Mutually Assured Destruction (MAD) discourages use.

• But deterrence does not fully explain why nuclear weapons haven’t been used.

Alternative explanation:

• Nuclear taboo (Nina Tannenwald):

  • A strong norm against using nuclear weapons.

  • Nuclear use is seen as morally unacceptable and illegitimate.

Key idea:
Both strategic deterrence and international norms help explain nuclear non-use.

What is meant by the erosion of the nuclear taboo?

• The nuclear taboo is the strong global norm against using nuclear weapons.

• Erosion refers to this norm becoming weaker over time.

Possible causes:

• Leaders using more aggressive nuclear rhetoric or threats.

• Normalization of talking about nuclear use as a policy option.

• Development of low-yield or “usable” nuclear weapons.

Key idea:
If the taboo weakens, nuclear weapons may become more thinkable or legitimate to use.