After this discussion of the factual development of German submarine warfare, I still have to deal with the accusations built up by the Prosecution from certain preparatory deliberations on the subject of the organization of submarine warfare.

Simultaneously with the combat instructions of 3 September 1939, whereby German submarines were ordered to adhere in their operations strictly to the Prize Ordinance, an order was prepared in the Naval Operations Staff decreeing action without warning in case the enemy merchantmen were armed. In addition to this, during the first days of the war there was an exchange of correspondence with the Foreign Office on the subject of declaring prohibited zones.

The Prosecution looks upon these two documents as proof of the intention to conduct a war contrary to international law from the very start. I, on the other hand, regard these same documents as proof of the fact that the Naval Operations Staff was fully unprepared for a war with England, and that it was only when the British had already declared war that they began to set about thinking in the most elementary manner on how such a war should be conducted. Since neither surprise attacks on armed merchant vessels nor the declaration of prohibited zones violate international law, a belligerent might well be allowed to consider after the outbreak of war if and when he wants to make use of these opportunities. As we know from the afore-mentioned orders of the British Admiralty, as early as 1938 a thorough study of all the possibilities resulting from the war upon commercial shipping had been made and elaborated for practical purposes.

This same standpoint holds good also for the memorandum of the Naval Operations Staff of 15 October 1939, which has been quoted several times by the Prosecution. Its very heading shows that it is a study: “Possibilities for the Intensification of Naval Warfare.”

In accordance with the heading, the memorandum provides an examination of the military demands for effective naval warfare against England, and of the legal possibilities for fulfilling these demands. The result was the order of 17 October 1939, decreeing the immediate use of arms against all enemy merchant vessels, since, as we have already shown, they had been armed and incorporated into the military system. Further intensifying measures were for the time being recognized as not yet justified, and the suggestion was made to wait and see what the further conduct of the enemy would be.

One sentence in this memorandum arouses special suspicion on the part of the Prosecution. It says that naval warfare must, as a matter of principle, be kept within the framework of existing international law. However, measures which might result in successes decisive for the war would have to be taken even if new laws of naval warfare were created thereby.

Does this really constitute a renunciation of international law? Quite the contrary. A departure from existing international law is made dependent only on two quite limited conditions: (1) A military one, namely, that measures are involved which are of decisive importance for the outcome of the war, that is, also of importance in shortening the war;[[24]] (2) a moral one, namely, the nature of the new measures makes them suitable for incorporation into the new international law.

The memorandum itself states that this would be possible only within the framework of the laws of military combat ethics and a demand is therefore made for rigid adherence without any exceptions to these ethics of warfare. Under these conditions there can hardly be any doubt as to the possibility of formulating new international laws.

The well-known expert on international law, Baron von Freytagh-Loringhoven says, and I quote:

“... always been war which has given its strongest impulses to international law. Sometimes they have been of a positive, sometimes of a negative nature. They have led to further development of already existing institutions and norms, to the creation of new forms or the reversion to old ones, and not infrequently also to failures.”[[25]]