The Supreme Commander of the Armed Forces
Berlin, 29 Nov. 1939
OKW/WFA Nr. 215/39 g.Kdos. Chefs. Abt.L I
Directive No. 9 Principles for the Conduct of the War against the Enemy's Economy.
In the war against the Western Powers, Great Britain is the driving spirit and the leading power of our enemies. The conquest of Britain is, therefore, the prerequisite for final victory.
The most effective means to achieve this is to paralyze Britain's economy through interrupting it at critical points.
The development of the situation and progress in our armament may, in the near future, create favorable, conditions for extensive warfare against the foundations of British economy. The necessary provisions must therefore be made as early as possible for striking a destructive blow at the British economy by concentrating suitable weapons of our Armed Forces on the most important targets.
The non-military means of warfare, complementary to the measures of the Armed Forces, will be put into effect according to special instructions.
- As soon as the Army has succeeded in defeating the Anglo-French field army and in occupying and holding a part of the coast facing England, the task of the Navy and the Air Force of carrying on warfare against the economic structure of Britain will become of prime importance. Cooperation of the sabotage and fifth column organizations is desirable.
- To the Navy and Air Force will fall the following joint tasks, enumerated here in the sequence of their importance:
Attacks on the main British ports of transshipment by mining and blocking the approaches to the harbors and by destroying vital port installations and sea locks.
In this connection the role of the mine-laying planes will be a very important one, especially with regard to the harbors. on the west coast of Britain, in narrow waterways, and estuaries.
- Attacks on British merchant shipping and against the enemy fleet protecting it.
- Destruction of British supplies of oil and of food in cooling plants and grain elevators.
- Interference with British troop and supply transports to theFrench coast.
- Destruction of industrial plants, the elimination of which is of decisive importance for the conduct of the war; above all of key-plants of the aviation industry and the factories producing heavy ordnance, anti-aircraft guns., ammunition, and explosives.
- Attacks on the main British ports of transshipment by mining and blocking the approaches to the harbors and by destroying vital port installations and sea locks.
The most important transshipment ports in the British Isles, which handle 95% of the foreign trade and could not be adequately replaced by others, are:
for imports of food, timber, and oil, and the processing therof.
These three harbors, handling 58% of England's peacetime imports, are of decisive importance.
for the export of coal.
The following may be considered alternate harbors, but to a limited extent and for certain goods only:
It will be necessary to watch continuously for any possible shifting in the use of these harbors. Besides it will be important gradually to compress and shift British foreign trade into channels which are within easy range or our naval and air forces.
French harbors will be attacked only insofar as they play a role in the siege or Britain, or if they are or importance as debarkation points for troops.
- In harbors which cannot be blocked effectively with mines, merchant shipping is to be paralyzed by sinking ships in the roadsteads and by destroying vital harbor installations. Special emphasis is to be laid upon the destruction or the great canal locks at the harbors or Leith, Sunderland, Hull, Grimsby, London, Manchester (Ship Canal), Liverpool, Cardiff, Swansea, and Bristol-Avonmouth. Particularly on the west coast these locks are very important in regulating the water level and, through it, the harbor traffic.
In preparing these actions it will be important to do the following:
- Continually to check and supplement the basic data available on British harbors, their installations and capacity, as well as information on the British war industries and supply depots.
- To rush the development or an effective method enabling planes to lay moored mines also.
- To provide a large supply or mines, sufficient for the increased demands or the Navy and Air Force.
- To coordinate the strategy of the Navy and Air Force, as to time and location.
These preparations are to be made as soon as possible. I request the Commanders in Chief of the Navy and the Air Force to keep me constantly informed about their plans.
I shall decide later as to when the restrictions still in effect in the naval and air war will be lifted. This probably will coincide with the start of the big offensive.
signed: Adolf Hitler