Berlin blockade: ussr blocks road, rail and canal access to german capital for. 11 months demanding w. allies withdrawal of deutschmark. Allies unable to agree on currency reform. Airlift supplies to city: signals commitment to germany w/o war. Nato formed april 1949-> article 5 is collective defense pact- attack against one is attack against all. Small tests of how much they will be committed to opposing ussr. Nato also sparked by 1948 czechoslovak coup d"etat. 1954: ussr suggests it joins nato to preserve peace and is rejected. 1955: w. germany incorporated into nato which leads to signing of warsaw. Pact (ussr, hungary, czechoslovakia, poland, bulgaria, romania, albania, e. Defensive: fend off attack and/or reduce damage. Deterrent: prevent adversary from initiating an unwanted action. Compellent: get adversary to stop (or start) doing something. Schelling: brute force requires no collaboration, used in traditional war vs. political force like coercion/deterrence.