Understanding Stalin's foreign policy requires examining his shifting approach to the unfolding Cold War. Up until 1945, he sought great power cooperation in Europe, but later rejected compromise with the United States for fear of exposing Soviet weakness. Stalin’s failed gambit for influence in Iran and Turkey showed the limitations of heavy-handed bullying of neighboring countries: in both cases, he had to retreat and retrench. Meanwhile, in Greece, Stalin shifted opportunistically from a cautious noninvolvement to increasing support for the Communist insurgency. But his Balkan strategy was complicated by an unexpected quarrel with Yugoslavia’s Josip Broz Tito, fueled by Stalin’s jealousy and mistrust. Stalin’s realization in 1947 that left-leaning coalitions that he sponsored across Eastern Europe were not electable marked a turning point towards confrontation with the West. Stalin began to prioritize security over legitimacy. This logic led him towards an attempt to dislodge the Allies from divided Berlin, resulting, by 1949, in a complete division of Europe.