As to the story itself, I need say only that I have tried scrupulously to avoid twisting any fact to prove a point; and I have cited no fact, even the most unimportant, without verifying it by reference to the original source. The description of the method of attack by the invading foreign armies is not based on any of the conflicting tales that have come to us from the European scene of war. In fact, the present war has been almost ignored. The foreign army statistics and other facts are based on undoubtedly authoritative official and semi-official publications issued during times of peace, on a study of the great peace maneuvers, and on information possessed by our own military experts. Similarly, in treating of our own army and its situation I abstained wholly from using any of the tempting material that has been made so freely available since the beginning of the agitation for military preparedness, and have used, instead, the simple and surely unbiassed facts presented to Congress in responsible official reports before the European War centered American interest on our own condition. The book will demonstrate for itself that the “story element” is not made to depend on invented battles or imagined catastrophes. Facing the fact that war is an iron game, wherein the moves are predicated inexorably on the possession of the material in men and appliances, the fiction takes no liberties save in trying to present a living picture of what such a war, falling on an army so unprepared, will be in such a country as ours. The technical soundness of the book is left by me to the verdict of technical experts. The story was planned, drafted, written and rewritten with the benefit of unusually authoritative assistance and under technical coöperation rarely granted to books of this nature. My thanks are due to men who gave freely of their knowledge, professional ability and time without even asking that credit should be given to them in return. THE AUTHOR. INTRODUCTION Let us be safe rather than sorry! Every scene so graphically described by the writer of this book will find its duplicate in the mind of the reader who has kept himself informed of the occurrences in the European fields of war. In war the law of Nations, conserving the laws of humanity, is superseded by the law of necessity which is invoked and interpreted as to life and property by the belligerent concerned, to excuse every act committed.