usually called blockade, and Nelson’s protest against the consequent confusion of thought is well known.  “It is not my intention,” he said, “to close-watch Toulon”; and again, “My system is the very contrary of blockading.  Every opportunity has been offered the enemy to put to sea.”  It is desirable, therefore, to adopt terms to distinguish the two forms.  “Close” and “open” express the antithesis suggested by Nelson’s letter, and the two terms serve well enough to mark the characteristic feature of each operation.  Close blockade, it is true, as formerly conceived, is generally regarded as no longer practicable; but the antithetical ideas, which the two forms of blockade connote, can never be eliminated from strategical consideration.  It must always be with the relations of these two forms, whatever shape they may take in future, that the strategy of naval blockade is chiefly concerned.

With regard to commercial blockade, in strict analysis it should be eliminated from an inquiry that concerns methods of securing command and postponed to that section of exercising command which deals with the attack and defence of trade.  It is, however, necessary to treat certain of its aspects in conjunction with naval blockade for two reasons:  one, that as a rule naval blockade is indissolubly united to a subordinate commercial blockade; and the other, that the commercial form, though its immediate object is the exercise of control, has almost invariably an ulterior object which is concerned with securing control; that is to say, while its immediate object was to keep the enemy’s commercial ports closed, its ulterior object was to force his fleet to sea.

Commercial blockade, therefore, has an intimate relation with naval blockade in its open form.  We adopt that form when we wish his fleet to put to sea, and commercial blockade is usually the most effective means we have of forcing upon him the movement we leave him free to attempt.  By closing his commercial ports we exercise the highest power of injuring him which the command of the sea can give us.  We choke the flow of his national activity afloat in the same way that military occupation of his territory chokes it ashore.  He must, therefore, either tamely submit to the worst which a naval defeat can inflict upon him, or he must fight to release himself.  He may see fit to choose the one course or the other, but in any case we can do no more by naval means alone to force our will upon him.

In the long run a rigorous and uninterrupted blockade is almost sure to exhaust him before it exhausts us, but the end will be far and costly.  As a rule, therefore, we have found that where we had a substantial predominance our enemy preferred to submit to commercial blockade in hope that by the chances of war or the development of fresh force he might later on be in a better position to come out into the open.  That he should come out and stake the issue in battle was nearly always our wish, and it was obvious that