If this were true, it is obvious that war with a strong naval combination would present difficulties of the most formidable kind, greater indeed than we have ever experienced; for since with modern developments the demand for fleet cruisers is much greater than formerly, the power of devoting cruisers to trade defence is relatively much less. It cannot be denied that at first sight the conclusion looks irreproachable. But on analysis it will be found to involve two assumptions, both of which are highly questionable. The first is, that the vulnerability of a sea Power through its maritime trade is as the volume of that trade. The second is, that the difficulty of defending sea-borne trade is also as its volume--that is to say, the larger the amount of the trade, the larger must be the force devoted to its protection. This idea indeed is carried so far, that we are frequently invited to fix the standard of our naval strength by comparing it with the proportion which the naval strength of other Powers bears to their sea-borne trade. It is hoped that the foregoing sketch of our traditional system of trade defence will avail to raise a doubt whether either assumption can be accepted without very careful consideration. In the history of that system there is no indication that it was affected by the volume of the trade it was designed to protect. Nor has any one succeeded in showing that the pressure which an enemy could exert upon us through our commerce increased in effect with the volume of our seaborne trade. The broad indications indeed are the other way--that the greater the volume of our trade, the less was the effective impression which an enemy could make upon it, even when he devoted his whole naval energies to that end. It is not too much to say that in every case where he took this course his own trade dwindled to nothing, while ours continually increased. It may be objected that this was because the only periods in which he devoted his main efforts to trade destruction were when we had dominated his navy, and being no longer able to dispute the command, he could do no more than interfere with its exercise. But this must always be so whether we have positively dominated his navy or not. If he tries to ignore our battle-fleets, and devotes himself to operations against trade, he cannot dispute the command. Whatever his strength, he must leave the command to us. He cannot do both systematically, and unless he attacks our trade systematically by sustained strategical operation, he cannot hope to make any real impression.