The American record for unpreparedness is 100 per cent unchallenged. Today's lesson is our costliest, since no longer is time allowed to catch up with the lag which our optimism and naturally peaceful attitude produced. The authors are convincing enough in their marshalling of facts:- necessity, in times of peace, to sustain permanent victory through eternal vigilance, constant improvement and standardization of aims, modification of tactic to meet changing conceptions of war, permanent manufacture of munitions by private industry on a small scale, and so on. The approach is technical -- kinds of rifles, tanks, etc., which may limit the book's market to specialists. And yet the style is repetitive, deliberately over-simplified, and occasionally talking down.