Japan's initial problem was to gain the mastery of the sea at the outset as an absolute essential; without it the employment of land forces would either be impossible or carried on at an enormous and perhaps fatal risk in the transportation of troops from the Japanese islands to the mainland Asia, or in supplying and reinforcing them when landed. The sea must be cleared of hostile warships before the war could really begin; and the complete success with which this problem was solved at surprisingly small cost rivals the brilliant achievements of the British navy which deprived the first Napoleon of any chance of success in war outside the European mainland, ruined his campaign in Egypt and made hopeless an attack upon the British Islands. [Sidenote: Japan's Main Ambition] Reviewing the results of the whole campaign, we can see that the main objective was the capture of Port Arthur; this largely from the military point of view, still more largely from the standpoint of sentiment, national pride, prestige with the world at large, and from considerations of statecraft. Japan had taken Port Arthur once before, from China, and was obliged to relinquish it to Russia. Its recapture this time no doubt meant more to the Mikado's subjects than any other result of the war; whatever else might happen, that was triumph enough. To the outside world Japan could hardly present a more striking proof of her prowess than the reduction of this fortress supposed to be impregnable; while in the final settlement at the end of the war its possession would mean an immensely important diplomatic point of vantage. From the strictly military viewpoint, the loss of Port Arthur took away from Russia the only hope of an effective naval base to which her Baltic fleet could safely resort, and from which she might hope to rebuild her shattered sea power. Vladivostock being manifestly ineffective, from its position to the north of Japan, as well as because it is ice-bound during a great part of the year. Oyama's campaign is thus seen to have been chiefly to give General Nogi a free hand at Port Arthur, keeping Kuropatkin well away from the chance of relieving the fortress. If the Russian army could be destroyed or seriously crippled, so much the better; but Oyama had evidently been quite content to take no risk of disaster to himself by trying to do too much. This seems to explain the apparent slowness and the ineffectiveness of his movements at times. He seems to have been satisfied to keep Kuropatkin simply in a position where he could do nothing to raise the siege of Port Arthur. The avowed purpose of Japan in beginning war was simply to drive Russia out of the Chinese dominions, which it had agreed to evacuate in the autumn of 1903, but had failed to carry out the agreement. The first year of war ended with the accomplishment of that purpose in as forward a state as could have been reasonably expected. [Sidenote: The Rival Armies]