What was the role of brinkmanship in eisenhower's foreign policy? why was it controversial?

Brinkmanship was a policy meant to actively oppose communism in foreign policy.  It was controversial because it heightened the tensions of the Cold War.

Context/detail:

John Foster Dulles was Secretary of State under President Eisenhower.  He held the office from 1953 to 1959.  He wanted a change from what had been the "containment policy" which the US had followed during the Truman Administration, as recommended then by American diplomat George F. Kennan.   Dulles felt the containment approach put the United States in a weak position, because it only was reactive, trying to contain  communist aggression when it occurred.

Dulles sought to push America's policy in a more active direction; some have labeled his approach "brinkmanship."  In an article in LIFE magazine in 1956, Dulles said, "The ability to get to the verge without getting into the war is the necessary art."  He wasn't afraid to threaten massive retaliation against communist enemy countries as a way of intimidating them.

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