SECURITY GUARANTEES PROVIDED BY INTERNATIONAL TREATIES AND THE ROLE OF INTELLIGENCE SERVICES: A REALIST–LIBERAL ANALYSIS

This article examines the structural limitations—such as unequal strategic interests, lack of enforcement mechanisms, and asymmetries in military capabilities—that constrain the effectiveness of security guarantees provided by international treaties. It focuses on how intelligence services, through covert informational mechanisms (e.g., espionage, disinformation, and clandestine influence), shape the credibility (i.e., perceived reliability and deterrent strength) and functionality (i.e., operational capacity to mobilize allies and respond collectively to threats) of collective defense commitments. Grounded in a comparative framework between liberalism and realism, this article analyzes how national interest, power dynamics, institutional trust, and intelligence cooperation intersect to either support or erode treaty-based security mechanisms. To empirically illustrate these dynamics, the article applies its theoretical lens to the case of the “drôle de guerre” (1939–1940), where the failure of France and the United Kingdom to intervene militarily in defense of Poland highlights how strategic restraint and intelligence considerations can undermine formal obligations—even in multilateral settings. The article also engages constructivist theory to reflect on how norms, identities, and collective perceptions influence the interpretation and credibility of security guarantees. Furthermore, it assesses the normative and operational need for democratic oversight of intelligence activities within alliances, proposing concrete mechanisms for aligning intelligence services with alliance commitments. Ultimately, the article argues that successful security guarantees rest on a synthesis of power, institutional design, and normative cohesion. By combining structural and ideational explanations, the study offers a more comprehensive understanding of why some treaties hold under stress while others collapse. The findings carry significant implications for the design of future security arrangements in a fragmented and increasingly contested international order.