Given that Hollywood luminaries have turned Darfur into a cause celebre, devoting an hour to understanding the roots of this horrific humanitarian crisis -- which has earned the dubious distinction of being the 21st century’s first genocide -- hardly seems like a lot to ask. Tracing the slow response over the last four years, “Frontline” zeroes in why the U.N. hasn’t intervened despite “Never again” pronouncements, in what author James Traub bluntly calls “a misbegotten province on the other side of the world of no strategic importance” to the United States.

Given that Hollywood luminaries have turned Darfur into a cause celebre, devoting an hour to understanding the roots of this horrific humanitarian crisis — which has earned the dubious distinction of being the 21st century’s first genocide — hardly seems like a lot to ask. Tracing the slow response over the last four years, “Frontline” zeroes in why the U.N. hasn’t intervened despite “Never again” pronouncements, in what author James Traub bluntly calls “a misbegotten province on the other side of the world of no strategic importance” to the United States.

The statistics remain harrowing: At least 200,000 dead; a dozen times that many forced to flee. Serial, almost ritualistic rapes and wanton brutality. “If the United Nations could die of shame,” the narration notes near the outset, quoting one writer, “it would have been dead years ago.”

At issue is the Darfur region of western Sudan, where the government unleashed a proxy militia, the Janjaweed, on rebel groups as well as the local civilian population. Amid mounting evidence of atrocities and half-hearted denials from the Sudanese government, the call has grown for the United Nations to step in.

The last four years, however, have produced only a string of toothless U.N. resolutions, while any decisive action has been impeded by Islamic countries, Russia and particularly China, protecting its business ties to Sudan. Fueled by growing frustration over U.N. impotence, what author Samantha Power calls an unprecedented grassroots movement has emerged, with performers such as Mia Farrow (among those interviewed here) waging a public-relations campaign that’s now being directed against the Chinese — vulnerable because of their interest in a hitch-free 2008 Olympics — to allow action regarding Darfur to take place.

Tales of murder, torture and rape punctuate the tragedy, but “On Our Watch” does more than simply rehash the carnage, instead highlighting a fundamental foreign policy conundrum in the nagging resistance to humanitarian missions without larger interests at stake.

In recounting this sorry history, “Frontline” joins a wave of Darfur-related documentaries, including Don Cheadle’s “Darfur Now” and HBO’s upcoming “Sand and Sorrow,” narrated by George Clooney. In doing so, PBS not only has put the issue in human terms but in a global context, providing a reminder of the grim reality that if you want the world to notice your plight, it helps to be sitting on either a large pile of arms or a gusher of oil.

Frontline: On Our Watch

Docu; PBS, Tues. Nov. 20, 9 p.m

Production

Produced by Canadian Broadcasting Corp. for WGBH/Frontline. Executive producer, David Fanning; producer, Neil Docherty.
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