IT IS a common theme among the pessimists that the world has relapsed since the armistice into a temper of nationalism which renders illusory the hopes and dreams of inter nationalism so widely entertained during the war. These two movements or moods, nationalism and internationalism, are regarded as opposing and mutually exclusive, and the very evident ascendancy of the former is too often unquestioningly accepted as involving, if not the final defeat, at least the indefinite postponement of the latter. If this were really so the outlook for mankind would be black indeed, for nationalism, not only in Europe and America but throughout the world, is clearly a rising power. But the belief that nationalism and internationalism are incompatibles, although superficially plausible, is based upon ignorance of men and nations and a complete misunderstanding of the two movements themselves. As this belief is widespread and is acting as a serious hindrance to the advance of a real understanding between nations, it may be worth while to subject it to the test of a brief analysis. Let us look first at the complaint brought by the disillusioned idealists and anti-nationalists against the post-war world. What is the general indictment that lurks behind the manifold grumb ling about the Balkanization of Europe, the unreasonableness of France, the commercialism of Britain, the impenitence of Germany, the self-assertion of the Little Entente states and of the British Dominions, and the recrudescence of isolationism and Monroeism in the United States? We are often told, when these topics are mentioned, that the world has relapsed from the principles and standards of internationalism into a state of blind and unreflecting nationalism. But, when we look at the facts, this explanation is obviously insufficient. If nationalism were really rampant in East-Central Europe how could the Little Entente between Czechoslovakia, Rumania, and Jugoslavia ever have come into existence or been maintained for three years? How indeed could these three states and their Polish neighbor, all of them inhabited by a variety of peoples, have succeeded in preserving their identity at all? Or how, if nationalism were the world's ruling passion, could the British Commonwealth,