The purpose of this thesis is to assess how a small nation like Costa Rica, which is committed to peace and lacks a military, is able to safeguard national security and territorial sovereignty while responding to a series of hostile external disputes with neighboring Nicaragua. It examines how Costa Rica’s actions and decisions in response to these disputes supports or impugns established tenets of international relations theory. Three case studies examine distinct periods of Costa Rican relations with Nicaragua, extending from the abolition of Costa Rica’s military in 1948 to the present-day. The findings are evaluated with respect to realist, liberal and constructivist theory. Costa Rica’s behavior best supports tenets of constructivist theory as it is undoubtedly influenced by socially constructed norms. These norms include a strong commitment to diplomatic dispute resolution, a general public perception that Nicaragua cannot be trusted and that some domestic capacity to employ force is an acceptable deviation from the nation’s commitment to diplomacy.

Subjects: Costa Rica; Nicaragua; conflict; liberalism; realism; constructivism; peace; United Nations; Organization of American States