John S. Dickerson is the senior pastor of Cornerstone Church and author of the forthcoming book “The Great Evangelical Recession: Six Factors That Will Crash the American Church ... and How to Prepare.”

...I found that the structural supports of evangelicalism are quivering as a result of ground-shaking changes in American culture. Strategies that served evangelicals well just 15 years ago are now self- destructive. The more that evangelicals attempt to correct course, the more they splinter their movement. In coming years we will see the old evangelicalism whimper and wane.

First, evangelicals, while still perceived as a majority, have become a shrinking minority in the United States. In the 1980s heyday of the Rev. Jerry Falwell’s Moral Majority, some estimates accounted evangelicals as a third or even close to half of the population, but research by the Notre Dame sociologist Christian Smith recently found that Christians who call themselves evangelicals account for just 7 percent of Americans. (Other research has reported that some 25 percent of Americans belong to evangelical denominations, though they may not, in fact, consider themselves evangelicals.) Dr. Smith’s findings are derived from a three-year national study of evangelical identity and influence, financed by the Pew Research Center. They suggest that American evangelicals now number around 20 million, about the population of New York State. The global outlook is more optimistic, as evangelical congregations flourish in places like China, Brazil and sub-Saharan Africa.

But while America’s population grows by roughly two million a year, attendance across evangelical churches — from the Southern Baptists to Assembles of God and nondenominational churches — has gradually declined, according to surveys of more than 200,000 congregations by the American Church Research Project....