Dunkirk was kind of confusing and stupid. Not enough story telling in it. Not a lot of explanation about what was going on. And I KNEW the basics of the historical event...can imagine how someone less knowledgeable of history would not be totally lost.
Funny, that's the one criticism I had for "The Longest Day", there was too much explaining in it, of course back then, people were more knowledgeable about what happened, so for those watching it today, it's probably just as well it was done the way it was.
I'm sure a lot of the guys who actually experienced it felt the same way...
The gimmick of 3 (4?) separate timelines converging, but intercut as if they were simultaneous, was too clever by half. That was the source of most of the confusion. A more linear plot would have been clearer, and provided back-story details which would have explained some of the dramatic points that were not resolved until the end of the film, or had to be inferred from the separate denouements of each plot line.