Several times during the course of Blood Diamond, characters explain the chaos, horror, and depravity around them by saying “TIA”, which is short for “This is Africa”. This doesn’t necessarily explain so much as it communicates that the characters using the phrase are cynical and indifferent to the fate of the Africans dying all around them. But judging by this movie, Director Edward Zwick is neither cynical nor indifferent, because Blood Diamond is a movie with a social conscience and a Serious Message. The message is a worthy one, which is why it’s really unfortunate that Zwick lets his pot of message interfere with ought to be a cracking good yarn.

Blood Diamond is set in Sierra Leone, during the civil war that ravaged that country in the 1990s. It has a good premise, and a dynamite opening. A peaceful African village is attacked by rebel soldiers of RUF, the Revolutionary United Front. Some of the villagers are killed, others mutilated by having their hands chopped off, and a fisherman named Solomon Vandy (Djimon Honsou), is seized and put to work as a slave laborer mining diamonds.

While toiling in a muddy river, Vandy finds a huge pink diamond that he realizes is worth a fortune, and risks his life to hide it. But his secret is soon out, and Vandy, who escapes when government troops attack the mine, finds himself teamed up with a white mercenary named Danny Archer (Leonardo DiCaprio), a small time diamond smuggler who served in the South African Defense Force in the days of Apartheid, and still calls Zimbabwe Rhodesia. Together they undertake a desperate attempt to recover the diamond, and rescue Vandy’s young son from the RUF, who have drafted him to be a child soldier.

Throughout the movie, Zwick hammers ad nauseam on the evils of the trade in “conflict diamonds”, stones taken from war torn countries, the proceeds from which can be used to buy arms. This gives him an opportunity to use some corporate villains. (Always safe and politically correct in Hollywood, which suffers from a villain shortage these days.) Zwick blames greedy diamond merchants for the war in Sierra Leone, and has a character explain that the practice of chopping off hands was introduced by the Belgians during the days of European colonialism. In fact, the Belgians never colonized Sierra Leone, it was a British possession, but then TIH. (This is Hollywood.) The sermonizing continues even through the closing credits, which are accompanied by a vomit inducing rap song about the conflict diamond trade.

In fact, the problems of conflict diamonds and child soldiers are very real, but it shouldn’t be necessary to subject the audience to speeches by UN officials at international conferences to make the point. Blood Diamond would be a long movie even without that. And surely at least some of the horrors that the RUF visited on Sierra Leone were due to the depravity and evil of its leaders and those who aided them, not a colonial empire that the sun set on donkey’s years ago.

When Zwick isn’t up on his soapbox, Blood Diamond is actually an entertaining movie. Shot partly in India, it offers gorgeous scenery, plenty of action, and some standout performances. Djimon Honsou gives an Oscar caliber performance as Solomon Vandy, driven, anguished, and desperate, but never overwrought. . DiCaprio is billed as the star of the movie, but it is Honsou who is the real center of the tale. Kagiso Kuypers, who plays his son Dia, is natural and unaffected, pulling off a believable transition from innocent boy to brainwashed killer. Arnold Vosloo, best known for the title role in The Mummy, makes a credible and menacing mercenary.

Leonardo DiCaprio turns in a good performance as Danny Archer, although he is not in Djimon Honsou’s league. He is certainly up to playing the lead in an action movie, but he clearly struggles with his Rhodesian accent. As a crusading journalist out to expose the trade in conflict diamonds, Jennifer Connelly is more problematic. She looks like a Cosmo girl who wandered into a war zone to do a fashion shoot, and she and DiCaprio spend a lot of time gazing meaningfully at each other, discussing the awfulness of what is happening in Africa. Whenever she’s on screen, Blood Diamond keeps threatening to turn into a chick flick with a high body count. The relationship between DiCaprio and Connelly never really goes anywhere. Connelly seems to there to provide DiCaprio with a piece of information that she might well have been unable to get in real life, and of course to look good doing it. (For that matter, a small time operator like Archer probably wouldn’t be walking around the African bush with a notebook containing the Swiss bank account numbers of the richest and most powerful diamond merchants in the world. Again, TIH.)

The combat scenes in this movie are quite good - chaotic, frightening, and at times surreal. The RUF are pretty accurately depicted, which may be a problem for some people. Anyone who has kept up with Africa’s wars (Including regular readers of Strategypage) knows that the wars in places like Liberia and Sierra Leone were quite beyond what any writer could invent. Others may simply not believe what they see. David Harewood, as a RUF commander called Captain Poison, seems like something straight out of the heart of darkness, but monsters like him were quite real . Since few of the combatants in Blood Diamond’s battle scenes are supposed to be trained soldiers, the fine points of combat weaponcraft are mostly irrelevant, but DiCaprio handles his AK well enough. (And it’s always a pleasure to see an action movie where the hero keeps his assault rifle on semi.)

Blood Diamond could have been a much better movie if Zwick had stuck to telling the story, and let it speak for itself. As it is, the movie is preachy and overly long. Blood Diamond isn’t a bad movie. In fact, at it’s best it’s pretty good. But it might well be better on DVD, with a thumb on the fast forward button.