Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Secretary of the Navy Josephus Daniels
Cablegram 28th July 1917.
To Secretary of the Navy Serial No. 145
Via Admiralty “L”
Sent Initials File No.
One hundred and forty-five. Information concerning proposed and actual movements of troops and troop supplies reaches France in various direct and indirect ways (stop) For example from War Department to its various representatives abroad and from French Military and Naval Attaches and from the various French missions in America (stop) Information concerning troop movements has even been heard in social circles (stop) The greatest danger of such information reaching the enemy lines in methods of communication and codes used and multiplicity of official or other communications exchanged. All experience of war in handling valuable government shipping and all war secret service experience points to necessity for restricting communications to a minimum and reducing personnel who are to be trusted with vital information involved (stop) I therefore submit that the most important measure that can be taken to insure maximum degree of safety for troop and troop supply shipping and in fact to provide against disaster is to require that all information concerning movements of such shipping proposed or actual should be transmitted safely through the Navy Department to me holding me responsible for informing all parties concerned on this side in sufficient time (stop) French Ministry Marine and General Pershing are in full accord with these recommendations (stop) The French Government is taking steps to stop future communications by their representatives in America (stop) But it is also necessary to take effective steps to insure that no information concerning the above is sent out of Washington by officials of any government or our own except through Navy Department which alone can be responsible for safety at sea.
Source Note: Cy, DNA, RG 45, Entry 517B. At the bottom of the document is typed, “Copy handed by Lt. Com. [John V.] Babcock/to General Pershing and Capt. [Richard H.] Jackson”.