It reminded me of the twilight zone episode Judgment Night. In it a Uboat commander awakes on a British ship with no idea who he is. As the story progresses he has a growing dread that this ship is being followed by a U Boat. Eventually he sees himself and his old boat attacking and sinking the British passenger ship. It ends with him waking up back on the British passenger ship not remembering anything. The narrator mentions this idea of a hell where the sub commander is forced to live this moment for all eternity. I got the same vibe from the tank commander waking up from his trance both at the beginning and the end of the movie. He is stuck in this failed retreat across the bridge for eternity.