I loved the historical aspect, the accomplishment of transporting 400,000 troops that were stranded. The depictions of the horror of war which we too often glamorize. The production crews operated in four countries, a logistical accomplishment.
The aerial dog fights were superb… with a small error: propellers continue to spin when the engine runs out of fuel. The movie showed a couple scenes of the propellers not rotating. Only pilots know these things.
Dunkirk is a cinematic achievement on several fronts.