It is difficult to imagine a place more physically and psychologically removed from the world economy, from centers of global influence such as Washington or London, than Warrap state (whose capital is Kuajok).

Here, wealth and status are counted mainly in cattle, which are essential for dowries (a reasonably desirable bride will bring 100 cows). The cattle must be fed even when families go hungry. The recent harvest was bad, but Dinka pastoralists don’t care much for farming anyway. About one-fifth of children at the nutrition program I visited were in the danger zone of malnutrition: when their upper arms grow skinnier than the circumference of a plastic bottle cap. Some malnourished 2-year-olds had never been strong enough to walk. Their skin hung loosely on backs and bottoms, like drapery.

People turn to clinics and hospitals only when the Spear Masters, traditional healers, have failed. Home birth is presumed. Contraception is almost nonexistent. According to a recent U.N. report, a 15-year-old girl living in South Sudan is more likely to die in childbirth than to complete school.

This is the definition of far away, of foreign, of the other. And it illustrates a broader point about global poverty. Nearly a billion people have risen out of poverty in the past 20 years. The original aim under the Millennium Development Goals to halve global poverty between 1990 and 2015 was met five years early, with China and India playing leading roles.

The poverty that remains, however, is increasingly concentrated in the hardest places to touch and reach: fragile states such as South Sudan. More than 50 percent of people living in extreme poverty are found in the 50 most vulnerable countries, according to World Vision. This group counts 70 percent of the world’s infant mortality and 77 percent of children who aren’t in school.

The president of World Vision, Rich Stearns — with whom I traveled in South Sudan — has been driven to expand operations in fragile states, in part by an algorithm his organization employs to determine the greatest need. “Fragile states are the future of poverty,” he says. “If we are not in these places, we are irrelevant.”

Stearns, who was once president of Lenox, the fine-china manufacturer, brings a businessman’s rigor to development theory. But investing in fragile states is not an obvious or easy strategy. It is expensive compared with development efforts in stable countries. “There is a higher cost per unit of change,” Stearns says. And collecting private donations is difficult. Child sponsorship isn’t an option. Because of security concerns, you can’t bring major donors to see progress. (At one checkpoint in Juba, Stearns and I found ourselves on the business end of a machine gun waved by an agitated teenager, which was exhilarating but not pleasant.)

The main problem, says Stearns, is that “man-made conflict does not evoke the same sympathy as natural disaster.” During four years of the Syrian crisis, World Vision has raised $2.7 million for its relief efforts. In five weeks since the Nepal earthquake, it has raised about $8 million.

So why go to the fragile states at all? For faith-based organizations, the answer is clear enough. Stearns feels called to “the margins, the broken places, the bleeding edges” as a distinctive element of Christian witness.

But most of the funding for relief and development in fragile states — often given in grants to nongovernmental organizations — comes from government, so there needs to be a justification beyond religious calling. The map of fragile states sometimes overlaps the map of urgent U.S. interests, as in Syria and the broader Middle East. The overlap is not as immediately obvious when it comes to South Sudan.

But regional chaos at the heart of Africa — and in the band of conflict along the 10th parallel — is not a matter of indifference to U.S. policy. Weak and failed states collect remora-like problems such as pandemic diseases, refugee flows, criminal gangs, mass atrocities, sexual violence and ideological radicalization. And a national purpose is served when the United States displays its animating values — on AIDS relief, for example, or help in fragile states — involving a clarification of its broader purposes in the world.

Working in fragile states reflects a commitment to fighting poverty where it is, as well as a passion for simple fairness. “How do you explain to a little boy or girl,” asks Stearns, “that we don’t want to help you because the politics of your country is too complex?”

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