The most difficult and trying responsibility of the President of the United States is dealing with the Communist tactics of crisis.
     Since World War II, both Mr. Truman and President Eisenhower have had to meet and oppose these Communist crises in almost every year of their administrations.
     You all remember how Truman managed. In the first series of crises rising out of the defeat of Germany and the conferences at Yalta and Potsdam, we saw all of the countries of Eastern Europe - Bulgaria, Rumania, Hungary, Poland, Czechoslovakia - fall behind the Iron Curtain.
     On the other side of the World, China fell and we found ourselves in the Korean war.
     President Eisenhower brought a halt to the Communist advances.
     In Asia, he ended the Korean war and stopped the Communist probings in Indochina and the Formosa Strait. He stopped them in the Middle East, and just last year and this he called Mr. Khrushchev's bluff on Berlin.
     This was the net result of the Paris Conference when Mr. Khrushchev found that he was up against a solid wall of resistance when he tried to force President Eisenhower to apologize for the U-2 incident:
     Had he gotten the apology, of course, it would have been an abject concession with nothing of substance in return.
     We can be certain that Mr. Khrushchev's next demand would have been agreement on withdrawal of western forces from Berlin.
     President Eisenhower did not weaken his position and give in to Mr. Khrushchev's demand.
     West Berlin remains free.
     This brings us to the main reason why the Communist tactics of crisis after crisis were successful against Mr. Truman's policies and failed against President Eisenhower's policies.
     You cannot deal with the Communists by giving them what they seem to want in trying to get them to negotiate or sign an agreement, much less to live up to it.
     You cannot deal with the Communists by drawing a line on our side of a piece of territory they are threatening and then say, as Mr. Acheson said about South Korea: "We won't defend what you are after now, but do not go a step farther."
     Both of these attitudes are attitudes of weakness. And both attitudes have been taken by Senator Kennedy in stating his foreign policy in this campaign.
     As to the Formosa Strait, he has said exactly what Mr. Acheson said in Korea: "We will not defend the line now under attack - the line of Quemoy and Matsu. But don't press us too far; we will defend the next line."
     If ever established as a part of our foreign policy, this is the kind of vacillation that might well bring war in the Formosa Strait.
     At the Paris Conference, he would have apologized or expressed regrets to Mr. Khrushchev in order to keep him at the conference table.
     This would have been an even greater invitation to disaster. Mr. Khrushchev's next demand would have been for satisfaction of his demands on Berlin.
     The show of weakness could only have led toward surrender in Berlin, and, quite possibly, in the end, to war in Europe.
     The policies of this administration have blocked the Communists' attempts to advance through crisis after crisis, but no one can stop the Communists from using these tactics.
     It is virtually the only way the Communists can advance.
     That is so because they have yet to win a single free election anywhere in the world.
     The next President of the United States - early in his administration - is almost certainly going to have to deal with a new Berlin crisis. Mr. Khrushchev can be expected to try again.
     Whether we have peace without surrender, or surrender, or even war, will be the fateful question in the balance.
     Senator Kennedy's answer - the answer of apology, the answer of retreat - is the wrong answer.