Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Major General John J. Pershing, Commander, American Expeditionary Forces
9 March, 1918.
My dear General,
My previous comments on the disadvantages of using French Channel Ports for discharge of troop transports or supply transports apply with greater force to the use of French Mediterranean ports. Vessels arriving on the French Atlantic Coast must pass through a submarine area that can be taken as approximately 150 miles. Vessels arriving in French Channel ports must pass through a submarine zone of 350 miles. Vessels arriving in French Mediterranean ports must pass through approximately 900 miles of submarine water.
Although submarine activity in the Mediterranean is not so pronounced as it is in the English Channel or off the French Coast, at the same time the number of escorting vessels in the Mediterranean is very limited and the methods of combating the submarine are also limited. Since vessels must pass for a much longer time through dangerous waters in the Mediterranean, it is much preferable to use the French Atlantic Coast or even the French Channel coast for our supply ships.
There is another marked disadvantage to using Mediterranean ports. At the present time all vessels leave America and proceed to Gibraltar direct, as there are no organized convoys. These vessels sailing singly are exposed to attacks by large submarines operating between Gibraltar and the Azores, and as a number of our storeships are unarmed an additional element of danger is introduced in using Mediterranean ports. The increased distance by using French Mediterranean ports rather than French Atlantic ports is about 1400 miles. This would result in the loss of approximately a week in time and would introduce some difficulties in providing fuel for the vessels, as fuel is very difficult to obtain in Mediterranean ports. I am of the opinion that the safest ports for our troop ships and supply ships are those on the French Atlantic Coast. These ports can be reached by a variety of open sea routes that are constantly shifted and the most dangerous areas can be passed during darkness so as to ensure the maximum protection to our vessels. I should strongly recommend that the French Atlantic ports be developed to their maximum capacity. I believe that all the money used in developing these ports will be wisely spent, and will result in giving our ships the benefit of the safest routes to France, as well as in a quicker return of shipping. So far as can be foreseen, it is likely that the approaches to the French Atlantic Coast will remain throughout the submarine war the safest in Northern European Waters. IF it is necessary to divert shipping away from the French Atlantic Coast during the building of additional piers, I recommend that French Channel ports be used rather than French Mediterranean Ports.
Very sincerely yours,
Source Note: Cy, DNA, RG 45, Entry 517B. Identifiers: “01. 10762” appears in the upper-left corner; “C/J/K/1/3/<9,>” and “11-14-25” in the right-hand corner, the former in columnar fashion. Document is addressed below close: “General John J. Pershing, U. S.A.,/Commander-in-Chief,/American Expeditionary Forces,/PARIS, France.”