Twenty percent of American adults claimed no religious preference in 2012, compared to 7 percent twenty-five years earlier. Previous research identified a political backlash against the religious right and generational change as major factors in explaining the trend. That research found that religious beliefs had not changed, ruling out secularization as a cause. In this paper we employ new data and more powerful analytical tools to: (1) update the time series, (2) present further evidence of correlations between political backlash, generational succession, and religious identification, (3) show how valuing personal autonomy generally and autonomy in the sphere of sex and drugs specifically explain generational differences, and (4) use GSS panel data to show that the causal direction in the rise of the “Nones” likely runs from political identity as a liberal or conservative to religious identity, reversing a long-standing convention in social science research. Our new analysis joins the threads of earlier explanations into a general account of how political conflict over cultural issues spurred an increase in non-affiliation.