A bracelet of prayer beads peeks out from under Eric Garcetti’s sleeve. The former mayor of Los Angeles got it in Bodh Gaya, India, where Buddha reached enlightenment under the Bodhi tree. Now he wears it whenever he can, he says, sitting down for an interview at the Montreal Climate Summit in April. There really is something quite equanimous in the way Garcetti talks about the deep political rift in the United States over low-carbon energy. Gar…