Cordon sanitaire (international relations)

The seminal use of cordon sanitaire (French: [kɔʁdɔ̃ sanitɛʁ]; lit. 'sanitary cordon') as a metaphor for ideological containment referred to "the system of alliances instituted by France in interwar Europe that stretched from Finland to the Balkans" and which "completely ringed Germany and sealed off Russia from Western Europe, thereby isolating the two politically 'diseased' nations of Europe." French Prime Minister Georges Clemenceau is credited with coining the usage, when, in March 1919, he urged the newly independent border states (also called limitrophe states) that had formed in Eastern Europe after World War I to form a defensive union. Such a system would both isolate the Soviet Union from Western Europe, and thus quarantine the spread of communism, while simultaneously threatening Germany's eastern border in the event of war, guaranteeing French security.

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