To hear it on the Brazilian street, Luiz Inácio Lula da Silva’s narrow win in Sunday’s presidential election was a catharsis. Nearly four years of errant government by the most rancorous right-wing leader since democracy returned in 1985 had left a country storied for its levity and grace embittered, diplomatically damaged and divided against itself. “Brazil is back,” the former president intoned in a victory speech to effusive crowds in downtown São Paulo and across the country.