The Soviets viewed this demand as unacceptable for it indicated that the United States was really taking too heavy a hand in determining what nations ought to adopt what specific form of government. In response, Stalin went on to create what Winston Churchill, never at a loss for words, dubbed the IRON CURTAIN. For Churchill: from Stettin on the Baltic to Trieste on the Adriatic, an iron curtain has descended across the continent. Behind that line lie all the capitals of the ancient states of central and eastern Europe -- Warsaw, Berlin, Prague, Vienna, Budapest, Belgrade, Bucharest and Sofia. From what I have seen of our Russian friends and allies during the war I am convinced that there is nothing they admire so much as strength and nothing for which they have less respect than military weakness.

Kennedy's speech on the Cuban missile crisis.