File No. 763.72111/226a

Memorandum issued by the Secretary of State1

MERCHANT VESSELS SUSPECTED OF CARRYING SUPPLIES TO BELLIGERENT WARSHIPS

1.
A base of operations for belligerent warships is presumed when fuel or other supplies are furnished at an American port to such warships more than once within three months since the war began, or during the period of the war, either directly or by means of naval tenders of the belligerent or by means of merchant vessels of belligerent or neutral nationality acting as tenders.
2.
A common rumor or suspicion that a merchant vessel laden with fuel or other naval supplies intends to deliver its cargo to a belligerent warship on the high seas, when unsupported by direct or circumstantial evidence, imposes no duty on a neutral government to detain such merchant vessel even for the purpose of investigating the rumor or suspicion, unless it is known that the vessel has been previously engaged in furnishing supplies to a belligerent warship.
3.
Circumstantial evidence, supporting a rumor or suspicion that a merchant vessel intends to furnish a belligerent warship with fuel or other supplies on the high seas, is sufficient to warrant detention of the vessel until its intention can be investigated in the following cases:
(a)
When a belligerent warship is known to be off the port at which the merchant vessel is taking on cargo suited for naval supplies, or when there is a strong presumption that the warship is off the port;
(b)
When the merchant vessel is of the nationality of the belligerent whose warship is known to be off the coast;
(c)
When a merchant vessel which has on a previous voyage between ports of the United States and ports of other neutral states failed to have on board at the port of arrival a cargo consisting of naval supplies shipped at the port of departure seeks to take on board a similar cargo;
(d)
When coal or other supplies are purchased by an agent of a belligerent government and shipped on board a merchant vessel which does not clear for a port of the belligerent but for a neighboring neutral port;
(e)
When an agent of a belligerent is taken on board a merchant vessel having a cargo of fuel or other supplies and clearing for a neighboring neutral port.
4.
The fact that a merchant vessel, which is laden with fuel or other naval supplies, seeks clearance under strong suspicion that it is the intention to furnish such fuel or supplies to a belligerent warship, is not sufficient ground to warrant its detention if the case is isolated and neither the vessel nor the warship for which the supplies are presumably intended has previously taken on board similar supplies since the war began or within three months during the period of the war.
5.
The essential idea of neutral territory becoming the base for naval operations by a belligerent is repeated departure from such territory by a naval tender of the belligerent, or by a merchant vessel in belligerent service which is laden with fuel or other naval supplies.
6.
A merchant vessel, laden with naval supplies, clearing from a port of the United States for the port of another neutral nation, which arrives at its destination and there discharges its cargo, should not be detained if, on a second voyage, it takes on board another cargo of similar nature.

In such a case the port of the other neutral nation may be a base for the naval operations of a belligerent. If so and even if the fact is notorious, this Government is under no obligation to prevent the shipment of naval supplies to that port. Commerce in munitions of [Page 620] war between neutral nations can not as a rule be a basis for a claim of unneutral conduct, even though there is a strong presumption or; actual knowledge that the neutral state, in whose port the supplies are discharged, is permitting its territory to be used as a base of supply for belligerent warships. The duty of preventing an unneutral act rests entirely upon the neutral state whose territory is being used as such a base.

In fact this principle goes further in that, if the supplies were shipped directly to an established naval base in the territory or under the control of a belligerent, this Government would not be obligated by its neutral duty to limit such shipments or detain or otherwise interfere with the merchant vessels engaged in that trade. A neutral can only be charged with unneutral conduct when the supplies, furnished to a belligerent warship, are furnished directly to it in a port of the neutral or through naval tenders or merchant vessels acting as tenders departing from such port.

7. The foregoing propositions do not apply to furnishing munitions of war included in absolute contraband, since in no event can a belligerent warship take on board such munitions in neutral waters, nor should it be permitted to do so indirectly by means of naval tenders or merchant vessels acting as such tenders.

Department of State,
  1. For circular note of September 19, 1914, to the representatives of belligerent governments, transmitting copies of this memorandum and of another giving rules for the treatment of armed ships, see ante, p.611