It seems, to me, that with Dunkirk Nolan finally addressed the problems his detractors usually have towards his work. I am one of those detractors, so I am very happy to see him change and adapt.
His stories often are based on convoluted ideas? This time is only fighting for survival.
He cannot shot action sequences, expecially close range ones? This film has none. In fact we don't even see the enemy (but we sure feel his presence).