Answer: Kennedy demonstrated his resolve to protect West Berlin.
Explanation: Upon his return home from the Vienna summit with Khrushchev, Kennedy demonstrated his resolve to protect West Berlin by calling up Army Reserve and National Guard units. Kennedy told his aides that the Communist-constructed wall was “not a very nice solution, but the wall is a hell of a lot better than a war.” In response to Khrushchev’s blustering, Kennedy and Secretary of Defense McNamara embarked upon the most intense arms race in world history, increasing the number of nuclear missiles fivefold and growing the armed forces by three hundred thousand men.