The Soviet conception of a future war did not change in Stalin’s last years, but an important shift of policy took place in 1949–50. Stalin decided to increase Soviet forces in Germany, to expand the Navy, and to build up the East European armies. These decisions reflected the growing tension in East–West relations. With the establishment of the North Atlantic Treaty Organization in April 1949, the United States was now formally committed to the defense of Western Europe, and the Western Allies began to build up their forces in Western Europe.116