If you think of it as a complete indictment of American culture, rather than the story of the criminal and the police officer who captures him, prosecutes him and then becomes his best friend, then "American Gangster," though still fairly boring, at least makes sense.
If, however, you do want the story of the criminal and the cop who captures him, prosecutes him and then becomes his best friend, you have a problem.
Basically, the movie just takes way too long to get anywhere. For a character-driven, anti-buddy movie, that's bad. But again, it's entirely possible that the film was hijacked by a deeper need to criticize the entire American edifice. There are little clues, like an older gangster's speech about how everything is going to hell these days and subsequent events proving him so utterly right. As in "Boogie Nights" and "Blow," similar stories of 1970s decadence and decline, things just keep getting worse and worse. In fact, it's a little disturbing how often we've had to keep telling ourselves the same story. But in this case, the 1970s clearly stand in for the 1990s. The project building in which a key police raid occurs is straight out of Jonathan Kozol. It is a 1990s project building, not a 1970s one. Among other things, those buildings were simply not that old back in the early 1970s. At that time, they were the solution, not the problem.
The movie therefore is a comment on the entrenchment of urban poverty, a comment which is made with such despairing ferocity that the filmmakers had to have been thinking of Abu Ghraib and Guantanamo as well. The lighting and setups are often so ugly that a person feels as though that is where we are. Ridley Scott appears to be telling us, "You Americans are such a bunch of savage thugs that the halfway decent among you have to join forces with the bad among you to hold the line against the even worse, and that's the best you can hope for." Unfortunately, Scott, in his understandable despair, neglected story values to such a degree that the viewer remains unengaged.
