Reagan believed that the American economy was on the move again while the Soviet economy had become stagnant. For a while, the Soviet decline was masked by high prices for Soviet oil exports, but that crutch collapsed in the early-1980s. In November 1985, the oil price was $30/barrel for crude, and in March 1986, it had fallen to only $12.Glenn E. Schweitzer, 1989 Techno-Diplomacy: U.S.-Soviet Confrontations in Science and Technology (1989) 63ff, 81.
