As I missed out on international art events this season because New York is so far away, all I could think of was how unlucky their curators are. You work on Venice or Documenta for a year or two or four. You start out researching when there’s a somewhat liberal president in the US and some island off the coast of Europe still considers itself part of the union. Though the war in Syria, the refugee crisis, and economic instability in the EU were already present, there’s still a feeling that this past year has served too many blows. And those large-scale exhibitions, years in the making, all opened to a great unknown. On Instagram, almost all the photos I see from Venice are of the same works, and I wonder how and if they respond to the current situation, whether there is a way for art not to seem detached. In New York, few of the exhibitions currently on view in commercial galleries and museums focus directly on contemporary politics. At Metro Pictures, Robert Longo’s show, “The Destroyer Cycle,” does just that. It’s comprised of large-scale charcoal-and-graphite drawings of riot cops in full gear, prisoners being led to a CIA …