LOS ANGELES — They were deployed by the Trump administration to combat “violent, insurrectionist mobs” in and around Los Angeles, but in recent days the only thing many U.S. Marines and California National Guard troops seemed to be fighting was tedium. “There’s not much to do,” one Marine said as he stood guard outside the towering Wilshire Federal Building in Westwood this week. The blazing protests that first met federal immigration raids in downtown Los Angeles were nowhere to be seen along