Papers Relating to the Foreign Relations of the United States, The Lansing Papers, 1914–1920, Volume I

763.72/2351½

The Secretary of State to President Wilson

Washington, January 7, 1916.

My Dear Mr. President: I have been thinking over, as I know you have, some means of placing submarine warfare on a basis which will prevent the horrors which have characterized it in the past.

I think that I appreciate the German point of view in regard to the danger to a submarine in attacking an armed merchant vessel, and have prepared a memorandum on the subject, which I enclose.

If the argument has merit the method of reaching a settlement on a basis which would safeguard human life would seem to be an agreement by Germany and Austria not to torpedo enemy vessels without putting the people on board in safety, provided they did not continue to flee, in consideration of an agreement by the Entente Powers not to permit their merchant ships to carry an armament.

I am sure the Teutonic Powers would agree to this, and I cannot see how the Entente Powers could reasonably object to such an arrangement, particularly in view of the fact that there is no case recorded to my knowledge of a submarine being destroyed by gunfire from a merchant vessel.

This plan would be practically a modus vivendi and could be made reciprocal on account of the activities of British submarines in the Baltic.

Would you advise my attempting to obtain such agreements?

Faithfully yours,

Robert Lansing

[Enclosure]

Memorandum by the Secretary of State on Armed Merchant Vessels and Submarine Warfare

[Washington,] January 7, 1916 .

The arming of merchant vessels is allowable when the armament is of a character which can be only used defensively.

When the statement as to the Status of Armed Merchant Vessels was issued in September, 1914, by the Department of State, the assertions contained as to the limitation of armament, which would give it a defensive character, was based on the use of naval ships in intercepting private commercial vessels. It was predicated manifestly on the defensive strength of ships of war, otherwise there would be no necessity to consider any restriction upon the armament carried by a merchant vessel.

Since the statement was issued the submarine has become a practical and successful agent in the capture and destruction of vessels of commerce, and, as a result, the principle on which the arming of merchant ships is declared to be allowable, should be applied to the new conditions created by this instrument of naval warfare.

Comparison of the defensive strength of naval vessels operating on the surface and submarines shows that the latter are almost defenseless in construction, their only means of protection from an enemy being their power to submerge. A merchant ship carrying a small calibre gun could destroy with one shot a submarine provided it came to the surface within range. Thus an armament, though falling within the limitations of defensive armament as previously defined, may be used effectively against a submarine. If it can be so used, it would appear to lose its defensive character.

The rule of visit, which is the only means of protecting private vessels engaged in commerce from being suddenly attacked and is the only means of putting in force the rule that the people on board shall be put in safety before a vessel is sunk, could hardly be required justly of a submarine, if the observation of the rule compels the submarine to expose itself to almost certain destruction by coming to the surface and offering itself as a target to a gun mounted on the merchant ship which it is required to hail and order to “lie to”.

If it is admitted that a submarine may be employed in intercepting enemy’s commerce and that in doing this it must hail vessels and put the passengers and crews in places of safety, it would appear to be a reasonable requirement that all merchant vessels should be without armament of any sort since a gun of whatever calibre and wherever mounted could be used offensively against a submarine on the surface with good prospect of destroying it.

A merchant vessel, therefore, carrying an armament should be treated by a belligerent or a neutral as an armed ship of the enemy and not possess the immunities attaching to private commercial vessels of belligerent nationality as now set forth in the rules of international law.