Secretary of the British Admiralty Walter F. Nicholson to Vice Admiral William S. Sims, Commander, United States Navy Forces Operating in European Waters
10th January 1918.
-: SECRET :-
The Force Commander, U.S.N.
The Admiralty have recently been considering the danger of submarine attacks on the Canadian Atlantic Coast, and they anticipate that enemy “U” Cruisers will probably be ready for service in the early Spring and are likely to operate off the Coast of America.
2.- The introduction of the convoy system has provided a strong incentive to the enemy to send submarines to attack the convoys at the Canadian ports of departure, and it is necessary that the convoy assembly ports should have adequate forces for the provision of a convoy escort for 200 or 300 miles from the port of departure, apart from fast trawlers and other trawlers and drifters required for patrolling the approaches and as additional escort in the more immediate vicinity of the ports. These latter will be provided by the Canadian Government in consultation with the Admiralty.
3.- It is estimated that at Halifax, N.S., and Sydney, C.B., the numbers of destroyers required will be four. For the patrol of the Gulf and River St. Lawrence a striking force, available to be sent anywhere without disorganizing the system f patrols and escorts, will be very advisable, which should include two destroyers, in addition to trawlers and miscellaneous patrol vessels. These destroyers cannot be provided by the British Navy at the present time, and I am to enquire whether it would be possible for six United States destroyers to be provided for the above service by the 1st April, 1918.
W. F. Nicholson.
Source Note: Cy, DNA, RG 45, Entry 517B.