I just bought, and watched, "The Longest Day" on Amazon.
I'd seen it before. It was made in 1962 by producer Darryl F. Zanuck, and stars approximately the entire population of Hollywood and large parts of Europe, I think. (Partial list: Edward Albert, Paul Anka, Richard Burton, Red Buttons... but I digress.)
It's not a great movie, by the standards of the ages. It's too long by half an hour at least, it's mawkish and sentimental, some of the acting is wooden, the movie itself credits three (!) directors, and it has that damn theme song that I'm going to have stuck in my head for a month now.
But it's worth watching for two reasons.
One is to see the battle sequences. There was no CG, and hardly any "special effects," in 1962. If you wanted to show a bunch of men running across a beach, getting shot at with machine guns, and tanks blowing up, you went out and got some men, tanks and machine guns. And blew them up, and filmed it. Some of these scenes are truly jaw-dropping. One of my favorites was seeing actual WW II fighter planes droning by from the deck of an actual WW II battleship. The planes back then didn't "streak by" the way planes do now - they bumbled past at what looks like the speed of a lawn tractor, giving the enemy plenty of time to shoot them down. Being a fighter pilot was practically a contact sport back then. People actually went to war in this equipment. In ships and planes that I'd think twice about going for a joyride in today. That took some stones.
The other reason to watch this movie is to appreciate the present. To realize that a bunch of people fought evil and a lot of them died. To realize that a bunch of people who maybe weren't all that crazy about each other in everyday life put aside their differences and fought a larger enemy. To realize that evil is still around, and still needs to be fought. I thought that was worth three hours of my time. So if you're looking for something to watch later, give "The Longest Day" a thought.
And think how much fighting is left to do.