A filmmaker who seeks to portray major events or periods in history has at least two objectives: being as faithful to the documentary record as possible, and producing a film that reaches as wide an audience as possible. While those goals aren't conflicting per se, it's easy to see how they can come into tension with each other: compressing years or decades into a film of two hours or less inevitably means that certain details and nuances -- including, perhaps, some very important ones -- will be omitted.
Take Zero Dark Thirty, Kathryn Bigelow's riveting account of the hunt for Osama bin Laden that was nominated for four Golden Globes and five Academy Awards. The film came under withering criticism, largely because of its contention that "enhanced interrogation" (i.e., torture) provided the information that led to bin Laden's capture. A stung Bigelow told Time that Zero Dark Thirty is:
...a film. So it's got actors. It's got sets. And editorial choices, composite characters, compressions, and ellipses -- ten years compressed in two-and-a-half hours. ... Where there's clarity in the world, there's clarity in the film. ... And where there's ambiguity in the world, there's ambiguity in the film. If you look at the experts on the subject matter... they all say that some information came out of the detainee program.
While it opened to nearly universal acclaim, Steven Spielberg's film, Lincoln, also elicited criticism. According to one scholar of 19th-century history, "African-American characters do almost nothing [in the film] but passively wait for white men to liberate them. ... [it] helps perpetuate the notion that African Americans have offered little of substance to their own liberation." Others argue that it exaggerates the extent to which emancipation came about because of the sorts of legislative compromises that the film depicts (and understates the extent to which it was brought about by radical action on the part of slaves).
While these criticisms are important, there's a difference between arguing that a filmmaker got the facts wrong -- as with Zero Dark Thirty -- and arguing that he/she should've emphasized X more, Y less, etc. In addition, whatever quibbles one might have with them, blockbuster films may spur viewers to learn more about important events in which they might not have otherwise taken an active interest. Given how much we lament Americans' lack of interest in both history and current events, films such as Lincoln should, on balance, be applauded. Concordia University's David Woodard put it well: "I always look at these films to see if a regular person who wasn't a 'Lincoln nut' would want to read a book about it after they watched the movie. I get the impression that most people who are not history buffs will now want to read something about Lincoln."