“Bushwick” opens with a beautiful aerial shot of New York — moving north over Brooklyn from Coney Island — that turns out to be the view from a helicopter gunship. The city is under attack, invaded not by a foreign or extraterrestrial army but by forces of secession from the southern United States. A young woman named Lucy (Brittany Snow), on her way to visit her grandmother, finds herself caught up in a new civil war.
This is not a bad premise. The idea that regional and ideological divisions might erupt into violent conflict doesn’t seem entirely far-fetched these days, and low-budget genre movies can often generate more political insight than their prestige-minded Hollywood cousins. But while “Bushwick,” directed by Cary Murnion and Jonathan Milott from a script by Nick Damici and Graham Reznick, offers reasonable technical competence — following shots that are as fluid and kinetic as expert video-game play — its storytelling is dimwitted and amateurish.
Fleeing black-uniformed snipers and storm troopers, as well as opportunistic street criminals, Lucy teams up with a burly janitor named Stupe (Dave Bautista), and they zigzag through the neighborhood that gives the movie its title. The name once signified a working-class black and Latino part of New York, but lately it has become synonymous with the artisanal, post-collegiate culture of 21st-century Brooklyn.
The filmmakers feign boldness in tackling national politics, but revert to coyness and caricature when it comes to local matters, gesturing toward a multiculturalism that isn’t even skin deep and sweeping gentrification under the rug. The civil war “Bushwick” imagines is mostly about white people, which kind of makes the movie a piece of historical…