11. That sabotage, i.e. acts of treachery before a declaration of war, are improbable, but that they may occur simultaneously with the first military hostilities, and that in any case they are not included in the present phase of the inquiry which deals essentially with military operations.
1. It is useless labour to work out in detail a series of _conventional_ operations. It is only necessary to work out real operations, i.e. the sort of operations an enemy might be expected to attempt. The numbers of these are limited: there are only four types.
[Sidenote: Except local co-operation (_see_ A. 11).]
2. First, sabotage, by which is meant acts of treachery perpetrated by persons or vessels in disguise before any declaration of war. Instances of these acts are given by Captain Hankey in his paper. They are an important study, but they do not touch the problems we are now examining, and they are therefore excluded for the present.
3. Secondly, a military raid on Blyth for the purpose of destroying Elswick.
We have hitherto assumed 10,000 men for Blyth-Newcastle; either more or less may be required. The force must be numerous enough to make its way in the face of sporadic opposition by unmobilised territorials and by the population, from Blyth to Elswick; to seize and destroy effectively the Elswick Works and the ships in the Tyne. It seems improbable that less than 10,000 men would be sufficient.
4. Thirdly, a raid of not less than 20,000 men on Harwich, with the object of stopping the regular army from going to France.
(_a._) The secret concentration and embarkation of 20,000 men.
(_b._) The destruction of the floating and land defences of Harwich by the escorting hostile squadron.
(_c._) The disembarkation of 20,000 men with a proportion of artillery before the British Fleet can arrive in sufficient force to give battle.
5. Fourthly, a landing in the Firth of Tay.
This is not worth doing unless the force landed is at least 35,000 men. It is assumed that war has begun before the enemy actually completed their embarkation; that the British Fleet has been forced to concentrate to the southward [Sidenote: It is almost hopeless to forecast what may happen during this critical time. No escorts could then be spared.] in order to fight a general battle with the German Fleet; that in consequence the northern waters of the North Sea are denuded of ships; and that the passage of fifteen or twenty independent transports to a fixed rendezvous, as suggested, will not be obstructed by any naval force which could not be overcome by the German warship escort. [Sidenote: I doubt if much in the way of escort could be spared. The enemy must be prepared to meet our entire superior force in North Sea.] In this case the forts are fully manned and the whole coast is alarmed and vigilant. The enemy’s transports must be escorted and protected by cruisers or old battleships; the opposition of the forts must be beaten down, and any resistance by local territorials on land must be overcome and quelled. The objective of the invaders is Glasgow and the Clyde. The whole six divisions of the expeditionary force have left England for a distant war. [Sidenote: On the whole this seems a very risky undertaking, but by no means impossible, and on the assumption above, quite worth trying.]