The closing years of the nineteenth century were also the closing years of the period of American isolation. The American doctrine of isolation was formulated by our first President: "The great rule of conduct for us in regard to foreign nations is, in extending our commercial relations, to have with them as little political connection as possible." For, he went on to say, "Europe has a set of primary interests which to us have none or a very remote relation." This was the rule that we lived by with only a brief interlude, during the Wilson Administration, until well into the Second World War.
Today that original American doctrine has been reversed. Now we act on the principle that the vital interests of Europe are the vital interests of America. But in addition to this, there is something radically new in our situation. If there were not something radically new, we could devote all our resources to working out the economic and social and political connections of that greater community to which Europe and the Americas belong. But while we must develop this greater community, the time we live in calls for more than that, and our problems are of a different kind.
It is not only that isolation has ended. It is that we have begun to live in the first years of the nuclear age. Ours is an epoch when the rivalry of two great social orders includes a rivalry in nuclear arms. We were very conscious of that fact during the crisis over Cuba. For in Cuba there was, for the first time in history, the kind of grim and deadly confrontation which could have led to thermonuclear war.