So I just saw this film, and decided to resurrect this thread to give some thoughts:
First off, holy ****.
Secondly, a great film from Nolan. Dunkirk doesn't seem like anything you would expect from Hollywood; it's not an American battle, it's not even a real military victory. Dunkirk ended with the withdrawal of the BEF and was followed by the French surrender just a few weeks later. In the words of Churchill, it was a "Colossal military disaster". None of the characters pull of any over the top heroics. There are some scenes of bravery and comradery, but it's always against the backdrop of tragedy. They manage to save a handful of lives against the loss of hundreds. The British are not portrayed as heroes, at least not in the traditional sense, the British Army doesn't stand tall and halt the hordes at the beaches. The entire time it's very clear the British are in disarray and desperate to just get off the beaches. They're a broken army, but not a broken people.
The Germans are portrayed entirely with aircraft, music and ambience, and their presence is pervasive. They're the enemy at the gate, the hordes swarming at the edge of the horizon, ready to spill over and annihilate everything in their path. And yet you never hear or see them beyond the wails of their sirens and the thundering of their artillery and bombs. It's clear their attacks are whittling away at the British, and causing intense fear and panic amid their victims, and that backdrop of near annihilation really makes the film seem so intense.
Ironically, on top of all of this, the sentiment I got at the end of Dunkirk was hope. Everything was going wrong for the British; they had been pushed back to the shoreline, their ships were being sunk, their aircraft blown out of the sky, and yet they survive. They live to fight another day. They make it back to Britain and prepare for the coming battle, the invasion that as we know will never come, but for the British after Dunkirk seemed like an inevitability. They were prepared, as it was said, to go on to the end.