- IS study: "Although no non-expansion pledge was ever codified, U.S. policymakers presented their Soviet counterparts with implicit and informal assurances in 1990 strongly suggesting that NATO would not expand in post–Cold War Europe if the Soviet Union consented to German reunification." http://www.mitpressjournals.org/doi/full/10.1162/isec_a_00236#.vyxwfhwlsfr 72 comments geopolitics