http://www.internationalbulletin.org/issues/2015-03/2015-03-122-barrett.html
"The American missions movement has experienced two distinct waves. A first wave of effort originated in the early nineteenth century during the Second Great Awakening and largely collapsed amid theological controversy after World War I; a second wave began after World War II and continues to this day.
[1] This article examines the role played by World War I in the demise of the first wave.
The foundation of the earlier mission efforts was a consensus on the twin goals of “civilizing” and “Christianizing.” Missionaries wanted others to adopt their religious beliefs and practices and, at the same time, to embrace Western political, educational, and societal systems. The latter desires were born out of earlier attempts to convert American Indians. Puritan missionaries to the Indians strongly emphasized evangelism, yet they found that conversions seemed to require that they first “civilize” the Indians—that is, teach them colonial arts, sciences, and culture.
[2] The missionaries thus considered education, democracy, health care, and economic growth to be complementing and tightly interwoven goals of missionary work.
[3]
Driving the movement were millennial expectations about the return of Jesus Christ. Postmillennial interpretations heavily influenced the early missionaries, as many foresaw a coming epoch of reason, peace, and godliness that would pervade the earth and lead to Christ’s return. In this view, mission work would inevitably succeed because the Bible had declared Christianity would reign supreme during the millennium. The millennium was within grasp if the missionaries would but reach for it. Significantly, the rallying cry and goal of the Student Volunteer Movement (SVM)—a major source of American missionary recruits between 1891 and 1920—was “The evangelization of the world in this generation.”
[4]
Crumbling Foundations
By the eve of World War I, however, the theological and strategic foundation for American mission work was under substantial pressure. Two of its key pillars, postmillennialism and the civilizing/Christianizing consensus, were crumbling. Mainline missionaries began discarding beliefs in divine intervention, spiritual salvation, and a literal millennial kingdom. Hope for societal progress remained, but it was centered on human efforts rather than divine will. “Belief in Christ’s return on the cloud was superseded by the idea of God’s kingdom in this world, which would be introduced step by step through successful labors in missionary endeavor abroad and through creating an egalitarian society at home.”
[5] The prevailing millennialism within the mainline churches, in other words, had removed any supernatural feature that stressed the workings of the Spirit in favor of the more secular civilizing advancements of education, health, technology, and democracy.
Writing in 1915, James Barton, the foreign secretary of the American Board of Commissioners of Foreign Missions (ABCFM)—one of America’s largest mission boards—publically voiced views that would have been unthinkable thirty years earlier. He asserted that missionaries no longer believed unequivocally that all non-Christian religions were false. “The modern missionary goes out with the purpose of conserving all true values in the religious thought, life, and practices of the people whom he approaches. . . . The missionary today is consciously face to face with the great national, social problems of the countries in which he is located. . . . The successful solution of these problems will produce a religious as well as a social revolution for the non-Christian world.”
[6]
The deepest and most dramatic change he noted was a secularized reinterpretation of Christian “salvation”"
So, liberalism lead to a Social Gospel without the evangelismn component and many liberal denominations shrunk.
