Let's revisit what is possibly the greatest speech ever made by a US president on the subject of peace, i.e., John F. Kennedy's commencement speech at American University in June, 1963. Kennedy was advocating for a nuclear test ban treaty which--against all odds--was ratified by the Senate in the summer of 1963, a few months before Kennedy's death.

It is hard for political leaders, including our presidents, to push for peace. They get pressure from generals, from political supporters, from the public and from military contractors. But Kennedy felt the urgent need for peace, since we had come so close to a world-ending war the previous October.

In this speech, he says:

"I speak of peace … as the necessary rational end of rational men. I realize that the pursuit of peace is not as dramatic as the pursuit of war — and frequently the words of the pursuer fall on deaf ears. But we have no more urgent task.

Too many of us think it is impossible. Too many think it is unreal. But that is a dangerous, defeatist belief.

It leads to the conclusion that war is inevitable, that mankind is doomed, that we are gripped by forces we cannot control. We need not accept that view. Our problems are man made . Therefore, they can be solved by man.

Let us focus instead on a practical, attainable peace, based not on a sudden revolution in human nature but on a gradual evolution in human institutions, on a series of concrete actions and effective agreements which are in the interest of all concerned.

Peace is a process, a way of solving problems.

With such a peace, there will still be quarrels and conflicting interests, as there are within families and nations. World peace, like community peace, does not require that each man love his neighbor, it requires only that they live together in mutual tolerance, submitting their disputes to a just and peaceful settlement.

And history teaches us that enmities between nations, as between individuals, do not last forever. However fixed our likes and dislikes may seem, the tide of time and events will often bring surprising changes in the relations between nations and neighbors.

So let us persevere. Peace need not be impracticable, and war need not be inevitable."