THE PRESIDENT: Well, your contention is, apparently, that any state at war has a right to declare such an operational zone as it thinks right and in accordance with its interests, and what I was asking you was whether the right to declare an operational zone, if there is such a right, does not depend upon the ability or power of the state declaring the zone to enforce that zone, to prevent any ships coming into it without being either captured or shot.
FLOTTENRICHTER KRANZBÜHLER: I do not believe, Mr. President, that there exists agreement of expert opinion regarding that question. In contrast to the blockade zone in a classical sense where full effect is necessary, the operational zone only provides for practical endangering through continuous combat actions. This practical threat was present in the German operational zone in my opinion, and I refer in that connection to the proclamation of President Roosevelt regarding the U.S.A. combat zone, where the entering of that zone was prohibited, because as a result of combat actions shipping must of necessity be continuously endangered.
THE PRESIDENT: The proclamation of the President of the United States was directed, was it not, solely to United States vessels?
FLOTTENRICHTER KRANZBÜHLER: I am referring to it only to establish proof of the German interpretation that this area was endangered, and practical danger seems to be the only legal and necessary prerequisite for declaring an operational zone.
THE PRESIDENT: Would you say that it was a valid proclamation if Germany had declared the whole of the Atlantic to be an operational zone?
FLOTTENRICHTER KRANZBÜHLER: Mr. President, I would say that at the beginning of the war that would not have been possible, for the German forces at that time, without doubt, did not constitute an effective danger to the entire Atlantic sea traffic. I am of the opinion, however, that with the increase in the number of U-boats on the one hand, and with the increase of defense by hostile aircraft on the other, the danger zone of course expanded, and therefore the development of this war quite logically led to the point where operational zones were gradually extended and enlarged.
THE PRESIDENT: Do you mean, then, that you are basing the power of the state to declare a certain zone as an operational zone not upon the power of the state to enforce its orders in that zone, but upon the possibility of danger in that zone?
FLOTTENRICHTER KRANZBÜHLER: Yes.
THE PRESIDENT: You say it depends upon the possibility of danger in the zone?
FLOTTENRICHTER KRANZBÜHLER: I would not say the possibility of danger, Mr. President, but the probability of danger, and the impossibility for the belligerent to protect neutral shipping against this danger.