There are at least two reasons why people might see the Cuban Missile Crisis in this way.
First, we can say it is praiseworthy from the standpoint of the world as a whole. In this way of looking at things, the crisis is praiseworthy because Kennedy and Khrushchev avoided a nuclear war. The Cuban Missile Crisis could easily have ended up escalating to the point where it became a full-blown war between the two superpowers. We can say that we should praise the fact that this did not actually happen.
Second, we can praise it from the point of view of the United States only. In this view, we can say that the crisis was a win for the United States. Kennedy was able to force Khrushchev into (at least publically) backing down without getting anything in return. The missiles were removed from Cuba and the US had a victory.
Thus, the crisis can be seen as worthy of praise both from the US point of view and from that of the world as a whole.