The former League members had fought against the war and American participation in it, and had taken the general position that the outbreak of the war should have been countered by a revolutionary general strike. When the United States entered the war in April 1917, they took the position that, inasmuch as the revolution had been betrayed by the reactionary Social-Democrats and syndicalists, the main task during the war was to organize the great unorganized masses into the trade unions. The trade unions, they held, were the all-important basic organizations that would one day emancipate the working class. The war situation, with the great demand for labor and the government's basic need for all possible production, presented an exceptionally favorable opportunity for such union-building work. This should be based on an active strike policy. Every other consideration in the war period was to be sacrificed to the central task of building the unions. Foster led this group.
This, of course, was a highly opportunistic conception. While it did not involve actual support of the war, it nevertheless was an incorrect compromise. It was a sort of economism, an attempt to by-pass the war and to focus the struggle upon immediate trade union questions. The very active unionizing and strike campaigns of the Chicago I.T.U.E.L. group did, however, conflict directly with the no-organizing, no-strike policies of the pro-war Gompers machine.
The Chicago group of militants were in a favorable position to get results in their aggressive unionizing campaigns. For several years they had been winning support in the Chicago Federation of Labor, and they had good working relations with the progressive Fitzpatrick-Nockels leadership. It was largely because of the work of this militant group that the C. F. of L. became the most progressive central labor union in the United States. The left forces, by their influence, made the C. F. of L. the national labor center in the big fight to save Mooney and Billings; it became the leader in the national labor party movement from 1917 on; it hailed the Russian Revolution and demanded the recognition of the Soviet government; it fought the Gompers machine on many fronts; and it became identified with every progressive cause. Significant of the left-wing influence in all this radicalism was the fact that when later on, in 1923, the left-center alliance in Chicago was broken, the C. F. of L. soon degenerated into a routine, conservative Gompers organization.
History of the Communist Party of the United States by William Z. Foster, International Publishers, New York, 1952, pages 137-138.