Claim. Per Paul Johnson, the “Seven Sisters” of American mainstream Protestantism — American Baptist Churches USA, Christian Churches (Disciples of Christ), Episcopal Church, Evangelical Lutheran Church of America, Presbyterian Church USA, United Church of Christ, and United Methodist Church — collectively lost between one-fifth and one-third of their members between 1960 and 1990, with the Methodists alone losing 1,000 members per week for thirty years.
Elaboration. Per 04-difference-between-populist-and-denominational, citing Johnson op. cit. pp. 968-9.
Johnson’s diagnosis: the Seven Sisters declined “chiefly because they forfeited their distinguishing features, or indeed any features.” An Episcopal Church official observer at the 1994 General Convention captured this: “The Episcopal Church is an institution in free fall. We have nothing to hold onto, no shared belief, no common assumptions, no bottom line, no accepted definition of what an Episcopalian is or believes.”
For Hendricks’s argument, this is the same dynamic identified in state-church-vs-upstart-denominations-1800-1850 continuing through the late 20th century: state-church-style institutionalism with diluted distinctives loses members; populist upstarts with sharp distinctives grow. The 1960–1990 evidence is the modern continuation of an 1800–1850 pattern.
For UC: a cautionary mirror. UC has internal pressure to soften its distinctives (True Parents, Blessing, sexual-purity teaching) in interreligious and political settings. Johnson’s framing predicts that softening would produce Seven-Sisters-style decline — the populist case is partly that UC must hold its distinctives sharper, not soften them.
See also. populist-church, state-church-vs-upstart-denominations-1800-1850