Economic Weapon: The Rise of Sanctions as a Tool of Modern Warfare

List of Key Chapter Titles

1. The Blockade Mechanism, 1914–1917
2. Sanctions Born from the Blockade Ethos, 1917–1919
3. The War of Peace, 1919–1921
4. Calibrating the Economic Weapon, 1921–1924
5. The World Police in Geneva, 1924–1927
6. Sanctionism and Neutralism, 1927–1931
7. Collective Security Against Aggression, 1931–1935
8. The Greatest Experiment in Modern History, 1935–1936
9. Blockade Phobia, 1936–1939
10. The Positive Economic Weapon, 1939–1945

Document Introduction

This research report delves into the origins and development of modern economic sanctions during the three decades following World War I. The study shows that economic sanctions did not emerge in a vacuum; their concept and mechanisms directly evolved from the comprehensive economic blockade imposed by the Allies (particularly Britain and France) against the Central Powers during World War I. This blockade, described by Britain's first Minister of Blockade, Robert Cecil, as "unprecedented," aimed not only to sever the flow of materials and finance to enemy nations but also developed in practice a complex set of global governance techniques, including raw material controls, blacklisting, import quotas, financial blockades, and preemptive purchasing. These wartime experiences convinced Allied policymakers that economic pressure was a "weapon" powerful enough to deter future wars.

The research reveals that the key institutionalization point for economic sanctions was the 1919 Paris Peace Conference. Driven by U.S. President Woodrow Wilson, Britain's Lord Cecil, and France's Léon Bourgeois, the logic of wartime blockade was transplanted into the newly established League of Nations, forming the collective sanctions mechanism stipulated in Article 16 of the League of Nations Covenant. The core innovation of this transformation was that it turned a coercive exclusionary tool originally used only in a state of war into a coercive instrument that could be applied in peacetime against an "aggressor," thereby blurring the traditional boundaries between war and peace. The report argues that the League of Nations' adoption of the economic weapon marks one of the most enduring innovations of twentieth-century liberal internationalism, with an impact far exceeding common perceptions.

The report is structured into three main parts, tracing the origins of the economic weapon, the construction of its legitimacy, and its role in the interwar crises. The first part provides a detailed analysis of the evolution from the World War I blockade to the post-war "peace blockades" imposed on Soviet Russia and the Hungarian revolutionary regime. It reveals how economic pressure became a cheap, long-range tool for shaping post-war Europe's political landscape (particularly in containing Bolshevism) and sparked widespread public debate on the ethics of economic warfare targeting civilians. The second part focuses on the 1920s, examining how the League of Nations and its member states attempted to institutionalize and legitimize this powerful yet imperfect sanctions system through technical bodies like the International Blockade Committee, and explored its practical application and imperial dimensions in various international crises (such as Balkan border conflicts and Turkish territorial disputes).

The third part assesses the role of the economic weapon in the global crises of the 1930s. The report re-examines the League of Nations' sanctions against Italy's invasion of Ethiopia—this "greatest experiment in modern history"—arguing that while they failed to save Ethiopia, they significantly drained Italy's economic strength and greatly intensified the fear of international blockade among other revisionist states (such as Nazi Germany and Japan), thereby driving their pursuit of autarky and territorial expansion. The report points out an under-examined connection between the threat and actual application of sanctions and the aggressive actions of fascist and militarist regimes in the late 1930s. Ultimately, the outbreak of World War II witnessed the combination of the "positive economic weapon" (such as the U.S. Lend-Lease Act) with blockade sanctions, a dual logic that was carried over into the United Nations system.

Based on archival materials from six countries—Britain, France, Germany, Switzerland, the Netherlands, and the United States—and publications in multiple languages, this study not only provides a detailed history of the origins of economic sanctions but also offers a profound historical perspective for understanding the widespread use of sanctions tools in today's globalized politics and their potential risks.