The failure of the larger hope was a blow to the "Easterners" who discerned in the Dardanelles the strategic key to victory in the war and expected to turn the argument against divergent operations by pointing to a converging advance from the Balkans upon the Central Empires. But the "Westerners," who maintained that the war could be won and could only be won in France and Belgium, were not much happier at the end of 1915. The British and French commands alike had subordinated the Dardanelles and Salonika expeditions to the needs of an autumn offensive on the West; and the argument between the two schools of thought is narrowed down, so far as the autumn of 1915 is concerned, to the question whether the troops we lost in September and October at Loos and in Champagne might not have been more effectively employed at the Dardanelles or Salonika. That they were not needed for defence in the West is obvious, since the line was held in spite of their loss. They were, in fact, mortgaged to an offensive which produced less strategical effect than the casualties in the East; for without the Salonika expedition, at least, Greece would have fallen completely under German dominion, and our control of the Ægean and our communications with Egypt would have been seriously imperilled. The controversy was an idle one so far as it was conducted on abstract principles, because war is an art in which success depends upon changing conditions which dictate one sort of strategy at one time and another at another. There were times when neglect of the West would have been fatal; there were others at which neglect of the East was almost as disastrous, and the autumn of 1915 belonged to the latter rather than to the former category. Neglect of the East would, indeed, have been not merely excusable but an imperative duty, had the situation in the West been what it was in the autumn of 1914 or spring of 1918. But there was no such necessity in September 1915: troops were not then withheld from the East to defend our lines in the West against a German offensive, but to take the offensive ourselves; and illusory hopes of success were based upon the known inferiority of German numbers in France due to their concentration in Russia.