Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Secretary of the Navy Josephus Daniels
SENT: June 28, 1917: TO: Secretary of the Navy:
THROUGH: State Department: (Mr. Shoecraft’s code)
Number fiftythree: With reference to problem and solution by Commander Schofield dated April seventeen stop Submarine attack is now almost exclusively with torpedo without submarine being seen at all before firing stop Actual extended experience demonstrates beyond question that neither men of war nor merchantmen can detect approach of submarine ten per cent of attacks stop This liberal estimate stop This fact independent of skill of half hour lookout or caliber or amount of armament or skill of guns crews stop Tactical discussions of gun encounters are futile stop: Destroyers and all types of war craft are not immune to attack any more than merchantmen except that submarine cannot expend torpedoes on them and accomplish his mission of destroying shipping stop: Another fundamental error in reasoning is discussion of any measure which cannot be applied immediately to all Allied essential shipping not in American plans which cannot affect present situation stop Protection of all Allied shipping in time – I repeat in time – is present mission stop Whatever efforts we can exert must be put into operation at once if they are to be effective stop Reliable submarines would be of great use to strengthen British submarine patrols and also as scouts ahead of convoys stop All submarines we can send to Irish Coast in time will therefore be invaluable in insuring success of convoy system and hence success of war provided these submarines are supplied from America and based upon their own mother ships.
Source Note: Cy, UK-KeNA, Adm. 136/656. Below “THROUGH:” someone has written “Admiralty.” At the bottom of the page is a columnar list of where copies of this cable should be filed.