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Admiral of the Navy George Dewey, President, General Board, to Secretary of the Navy Josephus Daniels










The strategic section of a war plan is in the form of an investigation. Its purpose is to find out what particular movement gives the greatest advantage; or what particular position is most desirable. The investigation of the Problem leads to the conclusion that Culebra is the key to the Western Atlantic and Caribbean region.2

To solve any strategic problem, whether particular or general the factors of strength of the forces, distances between them and the times to move across those distances must be given.



The distances are shown on the strategic chart; the times are those resulting from a speed of ten knots.

The forces are those given in the following tables in which Blue is at first inferior but ultimately superior to Black.


Blue  Forces.

The Blue forces are designated as the A fleet, the B fleet and the C fleet.

A  Fleet

11 – Dreadnoughts                  1 – Hospital Ship

3 -  Battleships                   1 – Transport

     Destroyer Flotilla Leader     1 – Repair Ship

1 -  Destroyer Tender              2 – Supply Ships

26 – Destroyers                    4 – Fleet Tenders (Tugs)

1 -  Submarine Tender              6 – Fleet Colliers

8 -  Submarines                    1 – Fleet Oiler

3 -  Mine Vessels                  1 – Mine Depot Ship

Time allowed to concentrate this fleet at Hampton Roads, coaled and ready for action from beginning of hostilities   7 days.


B  Fleet

11 – Dreadnoughts                  1 – Hospital Ship

4 -  Battleships                   2 – Transports

3 – Armored Cruisers               1 – Repair Ship

4 -  Cruisers                      2 – Supply Ships

26 – Destroyers                    4 – Fleet Tenders (Tugs)

Destroyer Flotilla Leaders    9 – Fleet Colliers

3 -  Destroyer Tenders             1 – Fleet Oiler

46 - Destroyers                    1 – Mine Depot Ship

1 – Submarine Tender

8 – Submarines

3 – Mining Vessels

Time allowed to concentrate the B fleet at Hampton Roads from beginning of hostilities      14 days.

This B fleet is the A fleet with the addition of vessels undergoing routine overhaul or vessels on special service readily available in full commission.


C  Fleet

12 – Dreadnoughts                  3 – Hospital Ships

21 - Battleships                   4 – Transports

9 – Armored Cruisers               4 – Repair Ships

9 - Cruisers                       4 – Ammunition Ships

3 – Destroyers Flotilla Leaders    8 – Supply Ships

3 - Destroyer Tenders              8 – Fleet Tenders (Tugs)

52 - Destroyers                    13 – Fleet Colliers

1 – Submarine Flotilla Flagship    9 – Fleet Oilers

1 – Submarine Tender               3-  Mine Depot Ships

9 – Submarines                     Necessary merchant fuel ships.

3 – Mining Vessels

20 – Fleet Scouts

Time allowed to concentrate the C fleet at Hampton Roads from beginning of mobilization          30 days.

The C fleet is the B fleet with the addition of all fighting vessels of the Navy whether in reserve or in ordinary, except those assigned to harbor defense; and of the necessary train made up of naval auxiliaries and merchant vessels chartered or purchased for this service.

The composition of the C fleet might be criticized as inadequate, out of proportion, or unsatisfactory in other respects; there are also no doubt various opinions to the time required to mobilize the fleet in its progressive steps. It is asked that these premises be accepted for the purposes of the argument, as what may be possible under present conditions, but not as what is necessary for a war plan that will lead to success. The conclusions drawn from the argument show that 30 days to assemble the C fleet lead to disaster; and that it is necessary to reduce this time to 14 days or less for any plan that will promise success.


Black  B  Fleet

19 Dreadnoughts               8 Transports (25,000 men)

18 Battleships                4 Mine Ships

4 Battle Cruisers             8 Repair Ships

3 Armored Cruisers            6 Hospital Ships

31 Light Cruisers             16 Supply Ships

141 Destroyers                4 Ammunition Ships

48 Submarines                 62 Colliers

264                           108

Time allowed to assemble the B fleet at Cuxhaven3 after hostilities began   7 days.

The same remarks apply to this B fleet of Black as to the fleets of Blue. It is considered a practical assumption for the purpose of the problem.



1.   Any normal distribution of the Blue fleet that makes possible the outbreak of war when the Blue fleet or part of it is in the Pacific must be avoided.

2.   The active A fleet must be maintained so as to be ready for battle in the Atlantic within seven days after possible declaration of war and re-inforced to strength of C fleet within 14 days after declaration of war.

3.   That Black main objective will be in the West Indies.

4.   That Black will advance after coaling at Azores or Cape Verde Islands toward this objective in the West Indies.

5.   That Blue will concentrate at base or advanced base in the West Indies.

6.   That Blue will not dissipate force in scouting wide areas in Atlantic; but concentrate information division over small areas to eastward of Caribbean.

7.   That Blue end in view will be to compel decisive engagement with Black near entrance to Caribbean; if possible, while Black is encumbered with train.

8.   That Blue will deny Margarita Anchorage and Samana Bay4 to Black by employment of submarines and mines. . . .




Development and Arrangement.


Introduction. Maps and Strategic Positions   pages  1-3

1. Political Situation – causes for war.        "   4-9

     Finances of war.

2. Black and Blue Resources available July 1,  "   10-15  

     1915 (For Naval Forces, see Appendix “A”)

3. Assumed conditions of problem – 3 cases      "  16-20

4. Tentative Mission assumed for Blue           " 20-21

5. Black Estimate of the Situation – 3 cases,    

     with decision in each case.                " 22-41

6. Black choice of Routes – 4 routes            " 41-46

7. Black Decision                               " 46

     Black Operations in the Far East           " 46

8. Blue Estimate of the Situation – 3 cases.

     Disposition of strength and courses of

     action open to Blue                        " 47-51

9. Blue Decision – 3 cases

     Case I                                     " 51

     Case II                                    " 52

     Case III                                     53-54

10. Final conclusion and Decisions              " 55

11.  Recommendations                            " 56

12. Blue Operations in the Far East             " 56a

     Supplemental Plan (War against Black

     and her allies)                              57

13. Causes of war                                 57-58

14. Black estimate and decision                   59

15. Blue estimate and decision                    60a-60b

Appendix A. Strength of Forces, Black and

     Blue, (March, 1916)                          120

Appendix B. Logistics of Blue and Black –

     fuel and train                               145

Appendix C. Tactical and Strategical Suggestions

     for Campaign in the West Indies and Caribbean  151

Appendix D. Studies and Conclusions of Naval

     War College.                                   165

Source Note: TD, DNA, RG 80, Entry 289 (Strategic Section). War Plan Black was prepared by the Naval War College under the auspices of the General Board of the Navy, headed by Admiral George Dewey. The basic War Plan Black was written in October 1910, See, DNA, RG 80, Entry 289. A request was made after the outbreak of World War I to update it and the update was written in February 1915. See, Dewey to Daniels, 28 January 1915, DNA, RG 80, GB425. The influence of this war plan on the commanding heights of the officer corps was deep set and long lasting. Secretary of the Navy Josephus Daniels approved a “Solution of Problem” that entailed fleet operations at Culebra over two months after the U.S. declared hostilities. See, Daniels to Badger, 26 June 1917, DNA, RG 80, Entry 289. The Strategic Section, which is over two-hundred pages in length, was composed in July 1915. There is a notation on the first page of the Strategic Section of War Plan Black was designated as “not a Plan but an ‘Estimate of the Situation’ upon which a Plan would be based. A preliminary study leading to a decision, but not a plan to carry out decision.” An additional note on the next page states that is to be treated as “CONFIDENTIAL” and that it was part of “War Portfolio No. 1, Reference No. 5-y.” The copy of this introductory section reproduced here is marked as “Copy No.1. (General Board Copy).” This is followed by a note that five copies of the plan were in circulation in July 1915 and directs that the whereabouts of these copies should be tracked.

Footnote 1: War plan designation by color began soon after the founding of the General Board of the Navy in 1900. Under this system, countries were assigned colors for war planning purposes. Thus, Great Britain was red; Japan was orange; Mexico was green; and Germany was black. Blue was used to designate the United States. See, Steven T. Ross, American War Plans: 1890-1939 (London: Frank Cass Publishers, 2002), 54, 78.

Footnote 2: Isla Culebra is a small (11 square miles) island belonging to Puerto Rico. It is some 17 miles east of the Puerto Rican mainland.

Footnote 3: Cuxhaven is a town in Germany situated on the North Sea at the mouth of the Elbe River.

Footnote 4: Isla Margarita is just off the coast of Venezuela and Samaná Bay is in the eastern Dominican Republic.