The history of the Great War in Europe and the forces that finally drove the United States to participate in that war have been told in ether articles of this volume. That story need not be repeated here. We need only to remem ber that in April 1917, after prolonged attempts to maintain American rights by diplomatic pro tests and expostulations, President Wilson went before Congress and advised that Congress de clare the recent course of the imperial German government to be in fact nothing less than war against the government of the United States. War was formally declared 6 April. Provision was soon made for the raising of an immense army, partly by calling the National Guard to the colors and also through the processes of a selective draft; training camps for officers were hastily built, and by the middle of May were filled with some thousands of eager young men. Money was voted lavishly for airplanes and various other things that modern warfare de manded. A few men were sent to Europe early in the summer of 1917, but it was the spring of 1918 before they were sent in large numbers. The American soldiers helped to stop the fierce drive of the Germans against Paris in the early summer of that year, and in the autumn they brilliantly executed plans for the seizure of the San Mihiel salient. In Sep tember American forces began the Meuse-Ar gonne offensive, the greatest connected series of engagements in which American soldiers have ever been engaged. Largely because of the courage of our troops and the terrific weight of the American armies which during these autumn months were hurled against the German line, the enemy were driven back until utter and overwhelming defeat stared them in the face. They applied for an armistice and on 11 No vember the terms of the Allies having been accepted hostilities came to an end. Soon after this President Wilson himself crossed the At lantic to Paris to represent, with four others, the United States at the Peace Conference. The Treaty of Peace with Germany was presented to the delegates of that country at Paris 7 May 1919 and after some delays and discussions was signed by the Germans. The treaty included, among other things, a provision for a league of nations in which America was to participate, and the terms of this treaty were subject to continuous discussion, not only in the Senate, when the ratification of the treaty was under discussion, but also in the country at large. The organization of the world to prevent war and to secure and develop peace had been proposed a number of times, especially from the beginning of 1916, and in various papers and speeches President Wilson had presented the desirability or necessity of such a consummation as the end, or perhaps the justification, of the whole struggle. The difficulties in reaching a decision
on the acceptance of the treaty and the League of Nations were enhanced by the elections of 1918. The Republicans obtained control of both houses of Congress, and there were conse quent difficulties arising out of the party sys tem in the way of hearty co-operation between the President and congressional leaders.
Among the most important internalpolitical developments in recent years are the addition of three new amendments to the constitution of the United States. The 16th amendment, already mentioned, gave Congress power to lay and collect taxes on incomes, from whatever source derived, without apportionment among the several States: in other words, Congress, in levying an income tax need no longer be bound by the clause in the constitution refer ring to °direct taxes° In the same year the 17th amendment was adopted, providing for the popular election of senators. By the early part of 1919 the 18th amendment providing for a na tional prohibition had been adopted by the requisite number of States and pronounced a part of the constitution. In accordance with the authority granted by the 16th amendment, an income tax law was passed by Congress, and during the course of the war a very large share of the government revenue was obtained in this way. One of the problems facing the United States at the end of the war was dealing with this subject of taxation, and especially of direct taxation on incomes. The whole economic problem of reconstruction occupied the atten tion of the people in the year after the close of actual hostilities. The government had taken charge of the railroads of the country not long after our entrance into the conflict and the economic perplexities resulting from the rise of prices and the increase of wages greatly augmented the difficulty of the economical man agement of the railroads and added to the tncacies of the whole national railroad problem.
Bibliography.— Adams, H., 'History of the United States of America' (9 vols., New York 1889-91); Dodd, W. E, editor 'Riverside His tory of the United States' (Boston 1915); Fish, C. R., of American Na tionality' (rev. ed., New York 1914); Hal A. B. (editor), 'The American Nation> ( vols., New York 1904 et seq.); McMaster, J. B.. 'History of the People of the United States from the Revolution to the Civil War' (8 vols., New York 18834913) ; Schouler, J., 'Eighty Years of Union' (New York 1903) ; Wiley, E, and Rines, I. E. 'The United States: The History of its Beginnings, Progress and Modern Development) (11 vols., New York 1916); Winsor, J., (Narrative and Critical History of America' '(1884-89), and the bibliographies appended to the various articles of this series.