Masterpiece or not, Casablanca definitely, for me, counts amongst the more enjoyable and genuinely affecting iconic films. I guess it's the pathos of war.

Casablanca's not fluffy like Breakfast at Tiffany's (all style and little substance); it has a steady, heartfelt undercurrent that is ultimately moral— stemming as much from situational forces and fundamental ideals as from the personalities evoked by Bogey and Bergman.

And that's what makes the film so strong for me: the love story is embedded in the time period. Love does not transcend all circumstances; and it shouldn't. There is something poignant and romantic about that.