"Given the right’s religious base, it’s not all that surprising that conservatives focus on moral transgressions—whether they violate God's divine law, America’s founding ideals of liberty, '50s-style norms of sexual behavior and good housekeeping, or other codes of conduct. But the left can be prudish and judgmental about the evils it holds in special contempt, too. On college campuses in particular, activists often take an almost religious approach to politics, rooted in a belief—sometimes stated, sometimes implied—in the irredeemable sin of America and its mainstream. Their work on vital issues gets diverted from real-world objectives and takes on the character of a church revival, with rituals to express its believers' sin and salvation, and a fundamentalist attention to language and doctrine.
"The late American philosopher Richard Rorty famously argued in his 1998 book, Achieving Our Country, that this inward-looking dogmatism and zealotry was a major problem for the left. To a self-destructive degree, activists rejected dissent and criticism of their hallowed principles. They alienated the uninitiated with their join-us-or-else self-righteousness, undermining public support for the important causes they cared about. They turned away with disdain from any whiff of political power, elitism, or national pride, thus depriving themselves of some of the tools they needed to bring about tangible changes to policy."
Victor Tan Chen at The Atlantic criticizes "the cultural left."