We may, however, I think, dismiss from our minds the belief, frequently advanced, and which is advocated so ably by Sir George Clarke, that such mutual support would tend in the future to exempt maritime commerce in general from the harassment which it hitherto has undergone in war.  I shall have to try for special clearness here in stating my own views, partly because to some they may appear retrogressive, and also because they may be thought by others to contradict what I have said elsewhere, in more extensive and systematic treatment of this subject.

The alliance which, under one form or another,—­either as a naval league, according to Sir George, or as a formal treaty, according to Mr. White,—­is advocated by both writers, looks ultimately and chiefly to the contingency of war.  True, a leading feature of either proposal is to promote good-will and avert causes of dissension between the two contracting parties; but even this object is sought largely in order that they may stand by each other firmly in case of difficulty with other states.  Thus even war may be averted more surely; but, should it come, it would find the two united upon the ocean, consequently all-powerful there, and so possessors of that mastership of the general situation which the sea always has conferred upon its unquestioned rulers.  Granting the union of hearts and hands, the supremacy, from my standpoint, logically follows.  But why, then, if supreme, concede to an enemy immunity for his commerce?  “Neither Great Britain nor America,” says Sir George Clarke, though he elsewhere qualifies the statement, “can see in the commerce of other peoples an incentive to attack.”  Why not?  For what purposes, primarily, do navies exist?  Surely not merely to fight one another,—­to gain what Jomini calls “the sterile glory” of fighting battles in order to win them.  If navies, as all agree, exist for the protection of commerce, it inevitably follows that in war they must aim at depriving their enemy of that great resource; nor is it easy to conceive what broad military use they can subserve that at all compares with the protection and destruction of trade.  This Sir George indeed sees, for he says elsewhere, “Only on the principle of doing the utmost injury to an enemy, with a view to hasten the issue of war, can commerce-destroying be justified;” but he fails, I think, to appreciate the full importance of this qualifying concession, and neither he nor Mr. White seems to admit the immense importance of commerce-destroying, as such.

The mistake of both, I think, lies in not keeping clearly in view—­what both certainly perfectly understand—­the difference between the guerre-de-course, which is inconclusive, and commerce-destroying (or commerce prevention) through strategic control of the sea by powerful navies.  Some nations more than others, but all maritime nations more or less, depend for their prosperity upon maritime commerce, and probably upon it more than upon any other single factor.  Either under their own flag or that of a neutral, either by foreign trade or coasting trade, the sea is the greatest of boons to such a state; and under every form its sea-borne trade is at the mercy of a foe decisively superior.