sentences:  Carter Doctrine
  
  The Carter Doctrine was a policy proclaimed by President of the United States Jimmy Carter in his State of the Union Address on January 23, 1980, which stated that the United States would use military force, if necessary, to defend its national interests in the Persian Gulf.It was a response to the Soviet Union's intervention in Afghanistan in 1979, and it was intended to deter the Soviet Union, the United States' Cold War adversary, from seeking hegemony in the Persian Gulf region.