By far the greatest reason for the ultimate success of the American war effort was the nation's economic resources, which it shared generously with its allies. The impressive performance of American military power and economic resources was matched, and sustained, by an ideological offensive led by President Wilson. This was not surprising in view of his keen interest, prior to 1917, in shaping the world to come after the war. Now that the United States was in the war, however, the aspirations of a neutral nation's leader developed into official enunciations of principles that were to guide the deliberations of the belligerents as they groped for peace. When the belligerents met in Paris at the beginning of 1919 to consider peace terms, American and Japanese forces were still in Siberia. Lenin, for his part, considered it prudent to retain some connection with the Western nations, in particular the United States, the country that would have the most to offer economically.