The argument is this:  that, as all strategic attack tends to leave points of your own uncovered, it always involves greater or less provision for their defence.  It is obvious, therefore, that if we are aiming at a limited territorial object the proportion of defence required will tend to be much greater than if we are directing our attack on the main forces of the enemy.  In unlimited war our attack will itself tend to defend everything elsewhere, by forcing the enemy to concentrate against our attack.  Whether the limited form is justifiable or not therefore depends, as Clausewitz points out, on the geographical position of the object.

So far British experience is with him, but he then goes on to say the more closely the territory in question is an annex of our own the safer is this form of war, because then our offensive action will the more surely cover our home country.  As a case in point he cites Frederick the Great’s opening of the Seven Years’ War with the occupation of Saxony—­a piece of work which materially strengthened Prussian defence.  Of the British opening in Canada he says nothing.  His outlook was too exclusively continental for it to occur to him to test his doctrine with a conspicuously successful case in which the territory aimed at was distant from the home territory and in no way covered it.  Had he done so he must have seen how much stronger an example of the strength of limited war was the case of Canada than the case of Saxony.  Moreover, he would have seen that the difficulties, which in spite of his faith in his discovery accompanied his attempt to apply it, arose from the fact that the examples he selected were not really examples at all.

When he conceived the idea, the only kind of limited object he had in his mind was, to use his own words, “some conquests on the frontiers of the enemy’s country,” such as Silesia and Saxony for Frederick the Great, Belgium in his own war plan, and Alsace-Lorraine in that of Moltke.  Now it is obvious that such objects are not truly limited, for two reasons.  In the first place, such territory is usually an organic part of your enemy’s country, or otherwise of so much importance to him that he will be willing to use unlimited effort to retain it.  In the second place, there will be no strategical obstacle to his being able to use his whole force to that end.  To satisfy the full conception of a limited object, one of two conditions is essential.  Firstly, it must be not merely limited in area, but of really limited political importance; and secondly, it must be so situated as to be strategically isolated or to be capable of being reduced to practical isolation by strategical operations.  Unless this condition exists, it is in the power of either belligerent, as Clausewitz himself saw, to pass to unlimited war if he so desires, and, ignoring the territorial objective, to strike at the heart of his enemy and force him to desist.