Civil War, set in a near-future, instead plays out with more subtle connections to today’s fractured politics and cultural splits Alex Garland’s films have vividly conjured a virus-caused pandemic (2002’s “28 Days Later”), an uncontrollable artificial intelligence (2014’s “Ex Machina”) and, in his latest, “Civil War,” a near-future America in the throes of all-out warfare. Most filmmakers with such a record might claim some knack for tapping into the zeitgeist. But Garland doesn’t see it that way. He’s dealing, he says, with omnipresent realities that demand no great leaps of vision. He wrote “Civil War” in 2020, when societies around...