STUDIES IN POLITICAL AREAS 299
have had to expand in order to become in reality "world pow- ers," i. e. t to span the earth ; and in this general process, every single country, even the smallest, has had its position continu- ally modified by the growth of the whole. Since the size of the earth's surface sets limits to this development, the zenith can be reached by only a few states at the same time. In like manner, the number of the smaller powers naturally depends upon the fifty-one million square miles which stand at the disposal of all. In this space there would, indeed, be room for two hundred countries the size of Germany or France ; but this wide expanse immediately shrinks when the five really great states of our time, England, Russia, China, the United States and Brazil, take their share in it, for these occupy almost the half. What remains is still large enough for quiescent possession which has been historically established, but small for the far-reaching plans of a new Alexander or Napoleon. The whole earth suffices for only a few great political exploits, and this so much the more, since it not only restricts the political areas, but also curbs the incentives to activity and growth. Russia cannot expand without clashing with the British or Chinese Empire. We ourselves have seen how, scarcely had Germany modestly enough entered the ranks of the colonial powers, but forthwith a sense of crowding went through the world, and the still undivided territory in a short time was taken up. Only upon a small planet like this could a surface of two million square miles form the base of a "genuine " great state. Therefore one nation pushes the other out of its position as a world-power. What England is today, Spain was formerly, just as in that narrow horizon upon which the western world had not yet risen, the Imperium Roma mint and the Persian Empire under Darius could not have existed side by side. In fact the succession in office, so to speak, of the "world-ruling" powers belongs to the most characteristic feature of ancient history. It is a phenomenon growing simply out of the question of space. In every age, however, we can call only that power a world-power which is strongly represented in all parts of the known earth, and espe-
