The Cold War ended where it began: in Eastern and Central Europe and in Germany. In 1989, the Soviet leadership ended the East-West stand-off by consciously failing to enforce its power monopoly in the region. The following year, Mikhail S. Gorbachev agreed to German unification and NATO membership for an enlarged Federal Republic. In doing so, the leader of the sinking Soviet empire gave in to Western maximum demands dating back to the early years of the East-West conflict. Although internal causes drove the Soviet surrender, Western policies contributed significantly to bringing it about. In any case, the Cold War's resolution resembled the forecast included in the most famous Western policy formulation since 1945: George F. Kennan's strategy of containment. In an article published in 1947, Kennan, then the head of the State Department's Policy Planning Staff, advocated a policy “designed to confront the Russians with unalterable counterforce at every point where they show signs of encroaching upon the interests of a peaceful and stable world.” In addition, Kennan wrote, “the United States has it in its power to increase enormously the strains under which Soviet policy must operate, to force upon the Kremlin a far greater degree of moderation and circumspection than it has had to observe in recent years, and in this way to promote tendencies which must eventually find their outlet in either the breakup or the gradual mellowing of Soviet power.” Kennan may not have been its “inventor,” and the policy was implemented in ways the author of the “X” article soon began to criticize, but containment did succeed in preventing the spread of Soviet influence across Western and Southern Europe. It also kept a large part of Germany out of Moscow’s reach.