Sort of a UK version of Black Hawk Down, in that the film is less concerned with character or plot and more concerned about place. The setting is everything: Where are these people, and how does that setting's history and geography inform the action? It's to the credit of '71 that it focuses more on suspense and less on carnage than Black Hawk Down does. This allows us to focus more on the burnt-out cars, dingy streets, and sad backyard clotheslines of 1971 Belfast. We get a sense that normal, innocent people lead actual lives amidst all the violence, which is more than can be said for Ridley Scott's intricately designed and orchestrated Mogadishu.
This is all to the good, as it keeps the screenplay's vision of society as one unending civil war from getting lost among all the thriller elements. '71 is least successful when it goes into thriller mode; director Yann Demange never develops any of his characters beyond the sketchiest outlines, so it's hard to care what happens to any individual in particular. They're not humans so much as character types wrapped around bundles of political and personal allegiances. "To them, you're just meat," one character tells a wounded English soldier. Given how undercooked Demange's characters end up being, it's hard to tell how ironically he intends that line to be read. Whatever the case, it sure doesn't make for involving drama or suspense.
Forget about drama and solid characterization, then. Focus instead on those dingy neighborhoods, where children play soccer next to scorched buildings and guns are hidden beneath loose floorboards. The Troubles were a time when brother was set against brother in all sorts of configurations: Protestant against Catholic, Irish against English, soldier against terrorist against civilian. Humanity was a civilization of Cains. It still might be. "We take care of our own" is a line that pops up a couple of times in '71. It's hard to ignore the double meaning in that sentence.