The original intention, with which the leading articles of the present collection were undertaken, was to elicit some of the lessons derivable from the war between the United States and Spain; but in the process of conception and of treatment there was imparted to them the further purpose of presenting, in a form as little technical and as much popular as is consistent with seriousness of treatment, some of the elementary conceptions of warfare in general and of naval warfare in particular. The importance of popular understanding in such matters is twofold. It promotes interest and induces intelligent pressure upon the representatives of the people, to provide during peace the organization of force demanded by the conditions of the nation; and it also tends to avert the unintelligent pressure which, when war exists, is apt to assume the form of unreasoning and unreasonable panic. As a British admiral said two hundred years ago, "It is better to be alarmed now, as I am, than next summer when the French fleet may be in the Channel." Indifference in times of quiet leads directly to perturbation in emergency; for when emergency comes, indifference is found to have resulted in ignorance, and fear is never so overpowering as when, through want of comprehension, there is no check upon the luxuriance of the imagination. It is, of course, vain to expect that the great majority of men should attain even an elementary knowledge of what constitutes the strength or weakness of a military situation; but it does not seem extravagant to hope that the individuals, who will interest themselves thus far, may be numerous enough, and so distributed throughout a country, as to constitute rallying points for the establishment of a sound public opinion, and thus, in critical moments, to liberate the responsible authorities from demands which, however unreasonable, no representative government can wholly withstand. The articles do not in any sense constitute a series. Written for various occasions, at various times, there is in them no sequence of treatment, or even of conception. Except the last, however, they all have had a common origin in the war with Spain. This may seem somewhat questionable as regards the one on the Peace Conference; but, without assuming to divine all the motives which led to the call for that assembly, the writer is persuaded that between it and the war there was the direct sequence of a corollary to its proposition. The hostilities with Spain brought doubtless the usual train of sufferings, but these were not on such a scale as in themselves to provoke an outcry for universal peace. The political consequences, on the other hand, were much in excess of those commonly resultant from war,—even from maritime war. The quiet, superficially peaceful progress with which Russia was successfully advancing her boundaries in Asia, adding gain to gain, unrestrained and apparently irrestrainable, was suddenly confronted with the appearance of the United States in the Philippines, under conditions which made inevitable both a continuance of occupancy and a great increase of military and naval strength. This intrusion, into a sphere hitherto alien to it, of a new military power, capable of becoming one of the first force, if it so willed, was momentous in itself; but it was attended further with circumstances which caused Great Britain, and Great Britain alone among the nations of the earth, to appear the friend of the United States in the latter's conflict. How this friendliness was emphasized in the Philippines is a matter of common report.