Most of the actual decline in believers from 2007 to 2014 was concentrated among Roman Catholics and the Protestant mainline, and among those most loosely tethered to religious faith. Evangelical Christians held pretty steady, which set up an odd chain of reactions. Secularists were pleased about the decline of Christianity. Some conservative Christians were pleased about the decline of theological liberalism. The latter is evidence of an old grudge.
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And this is what the Pew study is describing: the advance, particularly among the young, of an appealing, powerful culture that has its own standards and values (expressive individualism, moral relativism, lifestyle liberalism) but no longer presupposes religious belief and finds traditionalism to be repressive. For much of the post-World War II period, saying you were a Christian was another way of saying you weren’t a Jew (those being the two available options). This left a large number of Americans identifying with a religious tradition they did not practice. The assumption of faith has gradually — now more rapidly — fallen away. There may or may not be a decline in Christian practice. But we are certainly seeing the collapse of casual Christianity and of religious belief as a civic assumption.
