There is only one reason to see “The Alamo,” and it is Billy Bob Thornton. His portrayal of Davy Crockett is magnificently vibrant, fully imagined, and so breathtakingly evocative of the essence of the American hero that it may be worth seeing the film just to spend some time with him. As he quietly asks to be called “David” while he signs autographs and answers questions about his famous exploits, as he asks a dying young soldier his name, and as he accepts defeat with spirit and grace, Thornton shows mastery of a range of conflicting emotions that is unforgetably touching.

In addition, the battle sequences are well staged, putting the audience in the center of the action.

And the movie has the grace to address the issue of racism, with slaves owned by the officers at the Alamo talking about whether they would be better off as Mexicans, because they would be free, and with Hispanic Texans explaining why they chose to fight the Mexicans.

Despite all of that, however, the movie just does not work. Reportedly cut down from an original running time of three hours, it feels jumpy and disjointed. It makes the fatal mistake of assuming that it is enough to put American icons on one side and a choleric popinjay of a general who wears a uniform out of a Friml operetta, barks at his subordinates, and preys on young women on the other. It isn’t. We do not seem to be at a moment in history — perhaps we never will be again — when it is easy for us to choose our heroes and villains in a war over land. This is not a fight about religious freedom or taxation without representation or stopping a despotic marauder. It is a fight over who will own the land that probably both sides took from the Native Americans. And it is hard to cheer for the independence of the “Texians” when we know they’re just going to end up part of America anyway.

Just in case there might be someone out there who forgot to remember the Alamo, the movie begins with shots of the carnage and a soldier crying, “They’re all dead! Oh, God!” Then we go back a year earlier to see how the Alamo, designed as a mission, has become a fort, “the only thing that stands between Santa Anna’s army and our settlements.” A new young commander is assured that “a good rifleman and a 12 pounder should hold it” because Santa Anna’s men would need to march 300 miles through the snow to get there. We cut to thousands of Mexican soldiers trudging through the snow, and we know what has to happen. We meet our cast of characters, including Jason Patric as Jim Bowie of knife fame with a strong heart and weak lungs in the Doc Holliday role of a consumptive who has seen it all and done most of it, too, Dennis Quaid as Sam Houston, who knows the price that must be paid for independence, and Patrick Wilson as a man who is looking for a second chance.

So do the men at the Alamo. The way they face their inevitable fate is stirring. But the narrative is so muddled and the pace so choppy that we never connect with the characters or their cause.

Parents should know that the movie has intense battle violence with many deaths. Everyone in the Alamo is killed (made clear at the very beginning of the movie). Characters drink and smoke and use some strong language, including insults like “catamite” that might be unfamiliar to today’s audiences. There is a sexual situation with a hint of coercion. A character refuses to free his slave, saying, “You’re my property until I die.”

Families who see this movie should talk about why it made such a difference when Travis picked up the cannonball. What did Travis mean when he said, “Texas has been a second chance for me. We will sell our lives dearly?” Why didn’t Travis and Bowie get along? Do you agree that “one crowded hour of glory is worth an age without a name?” How did Crockett’s understanding of what he represented to his fans affect his decision about how to respond? How did the white and non-white characters see their priorities differently? How does this story relate to current conflicts in Israel, Iraq, and Afganistan?

Families who enjoy this movie will enjoy an early and less historically accurate 1960 version also called The Alamo, with John Wayne as Davy Crockett. They should read up on the legendary characters like Jim Bowie, David Crockett, and Sam Houston and discuss how each generation filters history with its own perspective. Families will also appreciate some other movies about famous defeats, including Errol Flynn’s highly fictionalized They Died With Their Boots On, The Charge of the Light Brigade, and Denzel Washington’s Glory.