To the countrymen of Nelson, and to those of his great interpreter, Mahan, these might at first sight seem very superfluous questions, for they, almost of natural instinct, should understand that strange but overwhelming force that has made them. To the Kingdom of Great Britain and Ireland, to the Empires that owe allegiance to the British Crown, to the United States of America, sea-power is at once their origin and the fundamental essential of their continued free and independent existence. And it is their predominant races that have produced the world’s greatest sea fighters and sea writers. It is to the British Fleet that the world owes its promise of safety from German diabolism bred of autocracy. It is to sea-power that America must look if she is to finish the work the Allies have begun. With so great a stake in the sea, Great Britain and America should have fathomed its mysteries. But, despite the fighters and the writers, the sea in a great measure has kept its secret hidden. In every age the truth has been the possession of but a few. Countries for a time have followed the light, and have then, as it were, been suddenly struck blind, and the fall of empires has followed the loss of vision. The world explains the British Empire of to-day, and the great American nation which has sprung from it, by a happy congenital talent for colonizing waste places, for self-government, for assimilating and making friends with the unprogressive peoples, by giving them a better government than they had before. And certainly without such gifts the British races could not have overspread so large a portion of the earth. But the world is apt to forget that there were other empires sprung from other European peoples--Portuguese, French, Spanish, and Dutch--each at some time larger in wealth, area, or population, than that which owed allegiance to the British Crown. In each case it was the power of their navies that gave each country these great possessions. Of some of these empires only insignificant traces remain to-day. They have been merged in the British Empire or have become independent. And the merging or the freeing has always followed from war at sea. It is the British sailors, and not the British colonists, that have made the British Empire. It is not because the settlers in New England were better fighters or had more talent for self-government, but because Holland had the weaker navy, that the city which must shortly be the greatest in the world is named after the ancient capital of Northern England, and not after Amsterdam. It was not England’s half-hearted fight on land, but her failure to preserve an unquestionable command of the sea that secured the extraordinary success of Washington and Hamilton’s military plans.