Which this article in First Things examines.
An excerpt.
“One of the key myths of the American Catholic imagination is this: After 200 years of fighting against public prejudice, Catholics finally broke through into America’s mainstream with the 1960 election of John F. Kennedy as president. It’s a happy thought, and not without grounding. Next to America’s broad collection of evangelical churches, baptized Catholics now make up the biggest religious community in the United States. They serve in large numbers in Congress. They have a majority on the Supreme Court. They play commanding roles in the professions and in business leadership. They’ve climbed, at long last, the Mt. Zion of social acceptance.
“So goes the tale. What this has actually meant for the direction of American life, however, is another matter. Catholic statistics once seemed impressive. They filled many of us with tribal pride. But they didn’t stop a new and quite alien national landscape, a “next America,” from emerging right under our noses.
“While both Barna Group and Pew Research Center data show that Americans remain a broadly Christian people, old religious loyalties are steadily softening. Overall, the number of Americans claiming no religious affiliation, about 16 percent, has doubled since 1990. One quarter of Americans aged 18-29 have no affiliation with any particular religion, and as the Barna Group noted in 2007, they “exhibit a greater degree of criticism toward Christianity than did previous generations when they were at the same stage of life. In fact, in just a decade . . . the Christian image [has] shifted substantially downward, fueled in part by a growing sense of disengagement and disillusionment among young people.”
“Catholic losses have been masked by Latino immigration. But while 31 percent of Americans say they were raised in the Catholic faith, fewer than 24 percent of Americans now describe themselves as Catholic.
“These facts have weight because, traditionally, religious faith has provided the basis for Americans’ moral consensus. And that moral consensus has informed American social policy and law. What people believe—or don’t believe—about God, helps to shape what they believe about men and women. And what they believe about men and women creates the framework for a nation’s public life.
“Or to put it more plainly: In the coming decades Catholics will likely find it harder, not easier, to influence the course of American culture, or even to live their faith authentically. And the big difference between the “next America” and the old one will be that plenty of other committed religious believers may find themselves in the same unpleasant jam as their Catholic cousins.”