She’s not about to weigh in on the filibuster, and you won’t see her hustling down the Promenade at the World Economic Forum, but Pema Chödrön, the 89-year-old Tibetan Buddhist nun, teacher and author, nonetheless has come to exercise a certain indirect sway on the American liberal elite. The vector of her influence is Ezra Klein , the New York Times podcast host and op-ed columnist. A devoted practitioner of Buddhist meditation, Klein, 41, lately has been immersed in Chödrön’s work, in particular her 2002 book, Comfortable With Uncertainty: 108 Teachings on Cultivating Fearlessness and Compassion, which he has read several times in the past year. A hint of his approach as a journalist is right there on page 1: “May we dwell in the great equanimity, free from passion, aggression, and prejudice,” goes part of the Buddhist prayer, known as the Four Immeasurables, that serves as the book’s epigraph. Not that Klein has anything against measurables.…