Collective effort can produce collective security and that if such effort is not made, it is because the will and the courage to make it are not there. It is therefore still more important than it ever was to realize that the real choice before us in this matter is: are we going to permit uncontrolled nationalism to dominate civilized Europe, or are we going to say that the European countries (I don't deal with the whole world, but it applies to that, too) are really part of one community with a common interest in international peace?

The Future of Civilization (1938)