If submarines are allowed to navies of the future, they must have a code of rules to work by. The code should be drawn up by people who know their subject, and who are also influenced in their ideas by the laws of chivalry and not by the ideas of the German War-Book. Apart from questions of right or wrong, unnecessary killing in war does not pay. Anybody can think of instances of this, but to suggest a case: if a U-boat had been sunk by our patrol vessels while she was in the act of picking up survivors from a torpedoed ship, well, the Germans would have lost a U-boat, but would have gained a splendid piece of propaganda. The patrol vessels could not be blamed, but the U-boat Service would have had a good grievance for the rest of the war. It is not only what you do in war that counts--the way you do it has a lot of influence also on the ultimate result. It is true that war is the negation of ethics, and that expediency is the ruling motive in all war-like acts, but it is a mistake to think, as the enemy did, that ruthlessness pays--decency may very often pay better. In war, a nation must take the blame for the acts of its militant servants; it sometimes pays to disavow such acts, and to sacrifice a subordinate, but in the main all blame must fall on the Government giving the orders. The essence of a military or naval force is discipline, and owing to that discipline all responsibility must in the end be shouldered by the Governments, except in the cases where individual officers have exceeded their orders or interpreted them to the dissatisfaction of their seniors. In our Submarine Service no boat left harbour without definite written orders, and the exact spirit in which her duty was to be carried out was fully understood. If any officer at any time had departed from his orders to the extent of "frightfulness," he would have found himself at once in a serious position: as nobody ever tried the experiment, I cannot quote any cases. I cannot do better, in speaking of the crews of our boats, than to quote from a despatch of Commodore Keyes (as he was then), written in 1914:-- "When a submarine is submerged, her captain alone is able to see what is taking place; the success of the enterprise and the safety of the vessel depend on his skill and nerve, and the prompt, precise execution of his orders by the officers and men under his command. Our submarines have been pioneers in waters which might well have been mined. They have been subjected to skilful and well-thought-out anti-submarine tactics by a highly-trained and determined enemy, attacked by gun-fire and torpedo, driven to lie on the bottom at a great depth to preserve battery-power, hunted for hours at a time by hostile torpedo craft....