🎲

5. Game Theory in Security and IR

Sep 15, 2025

Overview

This lecture introduces game theory as a framework for analyzing strategic decision-making in adversarial and cooperative situations, especially as applied to security studies and international relations.

Introduction to Game Theory and Security Studies

  • Security studies often analyzes adversarial relationships using models from social science.
  • Most introductory models focus on two participants in a dichotomous (two-sided) setting.
  • Game theory underlies many of these models, focusing on strategic thinking to maximize advantage.

Basics and Key Examples of Game Theory

  • Game theory is about predicting and responding to the actions of opponents in a strategic setting.
  • In game theory, new information and moves continually reshape the possible outcomes.
  • The classic "Princess Bride" scene illustrates rational decision-making and how unforeseen variables can disrupt plans.

Zero-Sum Games and Examples

  • Zero-sum games are situations where one participant's gain is another's loss.
  • Tic-tac-toe is a simple zero-sum game where players aim to win or at least block the opponent from winning.
  • Chess is a complex example where every move creates new variables and options.

Nash Equilibrium and Non-Zero-Sum Games

  • John Nash introduced the idea that self-interest is flexible and influenced by changing "governing dynamics."
  • The Nash equilibrium is a state where no participant can improve their outcome by changing only their own strategy.
  • The "A Beautiful Mind" bar scene demonstrates how collective outcomes can benefit all, not just individuals.

The Prisoner's Dilemma

  • The prisoner's dilemma pits individual self-interest against collective benefit, with options for cooperation or betrayal.
  • Four outcomes exist: both remain silent, both inform, one informs while the other stays silent, and vice versa.
  • Rational actors are most likely to inform, accepting a suboptimal outcome to minimize personal risk.

Rational Decision-Making and Probability

  • People must identify all available options and evaluate both their own and others' interests.
  • The Monty Hall game show problem shows that probability and reevaluation based on new information can change strategy.
  • Functional rationalization involves adjusting decisions as scenarios evolve.

Applying Game Theory to International Relations

  • Game theory assumes states act in their self-interest to maximize advantage and avoid worst-case outcomes.
  • In complex, multi-player scenarios, participants seek the best available outcome, even if not ideal.

Key Terms & Definitions

  • Game Theory — the study of strategic decision-making among rational actors.
  • Zero-Sum Game — a situation where one person's gain equals another's loss.
  • Nash Equilibrium — a stable state where no player can benefit by changing strategy alone.
  • Prisoner's Dilemma — a scenario where individual self-interest leads to a worse outcome than mutual cooperation.
  • Governing Dynamics — changing factors that influence self-interest in game theory.
  • Functional Rationalization — adapting goals and strategies based on updated scenarios and outcomes.

Action Items / Next Steps

  • Review returned homework and check posted grades.
  • Compare essay feedback with the sample Conley essay in course content.
  • Contact the instructor with any questions about summaries or assignments.