Josephus Daniels to Woodrow Wilson

Replying to your letter of the 23d instant in reference to the plan submitted by Mr. Frank J. Sprague for limiting the activities of German submarines in the present war I have to say as follows:Mr. Sprague's plan, in brief, is to build immediately large numbers of a special type of seakeeping boats of about 145 tons displacement, 159 feet in length, speed of from 20 to 25 knots and cruising radius of 3000 to 3500 miles. These vessels to be armed with one or two 3-inch (14-pdr.) and a few smaller guns, 50 depth bombs and 12 “dwarf” torpedoes of a type much smaller than those now used in our torpedo vessels.
When built these torpedo chasers are to be used, in conjunction with the destroyers and other vessels now employed against submarines, to guard certain “lanes” leading to the principal ports of entry and departure abroad and at home and extending several hundred miles to sea.
All who have given the problem of successfully combating the submarine menace consideration, are convinced of the necessity of large numbers of seakeeping surface vessels to meet it. All agree that the present type of torpedo boat destroyer is the best type for this purpose yet developed, and all would doubtless agree that if a smaller and more quickly constructed type, able to accomplish its work, could be obtained in much less time than can the destroyer, such a type should be produced as soon as possible. Whatever the method adopted for searching out submarines, – patrol, convoy or guarded lanes – larger numbers of small craft than are now available are urgently needed and time is of the utmost importance.
It was for these reasons that the Navy Department adopted the 110 foot motor boat of about 66 tons displacement of which 360 are now under construction. It was, however, fully recognized at the time that building these vessels was only justified by the emergency; that they were too small to keep the sea in bad weather or to carry as heavy an armament as the later submarines and, further, that their cruising would have to be confined to such areas as would enable them to quickly reach a port of refuge from bad weather.
The 159 foot boats proposed by Mr. Sprague would be better sea boats, would have greater speed and cruising radius than the 110 foot boats, but even if it should be proved that they could safely keep the sea in Atlantic winter gales it is as certain as any untried thing can be that they could not hold station as “lane” guards under such conditions. A heavy gale would scatter them widely and leave the “lane” unprotected until they could, perhaps after many days, resume their stations. The seagoing submarines of the enemy, ranging from 800 to 2000 or more tons, would ask nothing better than an established and unguarded “lane” with a continuous procession of valuable ships passing along it. They would no longer have to hunt for ships, easy as the task now seems to be, but would soon learn exactly where to go and lie in wait.
These boats, while too small for heavy, offshore work, would still be valuable for inshore patrol. They are, however, too small to meet the larger submarines, armed with 2 or 3 5.9” guns, which outrange the one or two 3” guns of the proposed batteries. The destroyers under construction will carry at least 4 – 4” guns, or 4 – 5” guns, if they can be procured in time; and will have sufficient speed to run down any submarine on the surface. From their greater speed, seakeeping qualities and heavy batteries it is considered that the boats under construction and in contemplation would prove more effective than a much greater number of the proposed boats of the Gardner type.
The proposal to form “sea lanes” to be used to the exclusion of other routes by cargo carriers bound to and from British, French and Italian ports, and patrol these lanes with surface craft, is not new. In various forms the proposition has come before the Department, and has received earnest and careful consideration. The scheme is practically working efficiently at the present moment between Dover and Calais, across the English Channel. It is a practical success there for three reasons: – the distance to be patrolled is very short, only 30 miles; the ends of the sea lane abut on the land, and the number of destroyers and other patrol craft, together with a number of submarines, is relatively great enough, when an important movement takes place across this narrow body of water, to have on each side several lines of protecting vessels, one beyond the other and very closely placed.
The three conditions which make the passage of the English Channel practicable are unfortunately not the conditions which will obtain in the localities where sea lanes are to be used to protect trans-Atlantic traffic. Mr. Sprague proposes to have a sea lane leaving, say, the English coast, projected out into the Atlantic, so closely patrolled by surface craft on either side that cargoes may pass between them in safety. It may be well to state in order some of the difficulties to be overcome in putting this plan into successful operation.
Considering the carrying trade to and from England alone, an investigation of this subject and the testimony of the Senior Naval Officer of the British Commission recently in this country, leads to the conclusion that the immense quantity of stores and munitions received daily in England, and the inadequate railroad transportation facilities there, makes it imperative to keep open several ports, instead of bringing the vast volume of seaborne supplies into one port. So, probably six lanes must be patrolled instead of one - at least to the main lane extending out into the Atlantic.
From all reports received from actual encounters with submarines, it is certain that the periscopes of submerged submarines can not usually be seen under daylight conditions in clear weather a greater distance than 1,000 yards; and this distance decreases to practically zero with failing light, mist, fog, or snow. It would therefore be necessary to have the patrolling vessels spaced not more than one mile (2,000 yards) apart, on each side of the lane in question in clear weather; and at night or in foggy weather, the patrol would be practically blind, so far as sighting periscopes is concerned. In fact, vessels have been torpedoed in open daylight, with destroyers on either beam, and close aboard, by submarines getting within 1,000 yards of the convoy and firing torpedoes without being seen.
Among the difficulties encountered by submarines in prosecuting their work are, first, to find the enemy's cargo carriers; second, to estimate the course and speed of the cargo carriers by tracking; and third, to then approach and fire when within torpedo range, preferably from a position somewhere forward of the beam of the target ship.
An easy determination of these usually unknown factors in the problem will be practicable for the enemy by the establishment of the sea lane. The double lines of picket boats between which the cargo carriers must pass will make a search for them unnecessary; the course of the target ship is also known by the direction of the lane; and a few minutes periscope observation of the disposition of picket vessels would give the desired ranges. Then, if anywhere the unavoidable action of the wind and sea had increased the intervals between picket boats, or at night or in bad weather, the submarine could easily approach within torpedoing distance, fire and totally submerge.
The length of the lane depends upon the number of patrol boats available. Assuming only three ports in England open to commerce, London, Bristol, and Liverpool, the sea lanes from these ports to the Scilly Islands, the beginning of the sea lane out into the Atlantic, aggregate 150 miles; and assuming patrols placed one mile apart, 300 patrol boats would be required. Patrols must be relieved regularly; it is a liberal assumption that not more than 2/3 of the force could be kept in position on the lanes – 1/3 being in port, coaling, overhauling, etc., and getting back to stations. Therefore, the lanes to the ports named would require 450 boats; and the 600 proposed would supply a lane only 50 miles long from the Scilly Islands to the westward. Or, assuming that the British could supply 450 patrols for the three lanes, the 600 to be supplied by the United States would project a lane only 200 miles into the Atlantic.Unless a patrol could be maintained across the Atlantic, 3,000 miles, the outer end of the lane must always remain the end, practically, of patrol protection; a point perfectly well known to the enemy, located as definitely as the Scilly Islands, as the point upon which submarine attacks were to be concentrated – and from there to other points of attack farther west.
If the boats in sufficient numbers could be obtained, there would still remain the absolute impossibility, recognized by all seamen, of keeping boats of the type proposed on station along a sea lane, in the heavy seas and strong gales to be encountered in the Atlantic, off the British Islands; and patrol boats would themselves be in great danger from submarines, their exact location being known, and as, necessarily, they would be keeping station at low speed.
After disposing of the 600 boats of the type proposed, there would still remain the ports in France, to which most war munitions and troops from this country must go, and also those of Italy, to be protected.
The practicability of building so many vessels, even of small size, in a short time, say twelve months, is gravely doubted and could only be done at all by the cessation of practically all other work in the ship and engine building yards of the country.
We are not prepared for such a programme, however simple, practicable and necessary it may seem to its advocates.
It may well be that in the not distant future, and suddenly, the United States fleet alone will be called upon to meet the enemy fleet in full strength and with this possibility in view we must proceed steadily to strengthen our fleet in all its various military units notwithstanding the immediate and serious peril of the enemy submarine operations. The future protection of our own national interests must be kept prominently to the front in all our plans.
It is a difficult problem. Whatever is done will provoke adverse criticsm from some quarter. The only safe and sane course to pursue is to build as quickly as possible as many anti-submarine craft of approved type as the facilities of the country will permit, using every possible effort, regardless of expense, to increase those facilities and at the same time to proceed with other necessary shipbuilding, both naval and commercial.
We have now 56 torpedo boat destroyers in commission, 66 under contract to be delivered by September, 1918, and 50 more are practically under contract now to be delivered ready for service by January 1, 1919, say 18 months. The Department is endeavoring to arrange for 150 more destroyers to be delivered at the earliest possible date, perhaps in 18 months or two years.Depth bombs of the character recommended by Mr. Sprague are already in use in our Navy.
The “dwarf” torpedo recommended is a new departure but if an efficient type of such torpedoes can be developed, as seems probable, it will be a valuable addition to the armament of vessels operating against submarines. Certainly it will be productive of greater caution in submarine operations where it is likely to be encountered. This matter is already under consideration by the Department.
As to the use of the “lane” system for minimizing submarine attack the matter had best be left to expert decision. The important thing is to provide the vessels with which to work. A system which might work well under one set of conditions or in a certain locality might not do well under other conditions or in other localities. Whether the patrol, the convoy or the lane systems, any or all, shall be adopted must be decided as experience and special conditions may determine.
I desire to express my great appreciation of Mr. Sprague's paper, the patriotic motives which inspired it and the thought and investigation evidenced throughout. Any recommendations emanating from a man of his ability and experience of affairs are deserving of the highest consideration and are always welcomed by the Department.

Sincerely yours,