According to President Bush, starving people in Darfur present "an unusual and extraordinary threat to the national security and foreign policy of the United States." (From this article)
Okay, it's more complicated than that. Obviously, the concern is with the ongoing conflict and instablility in the region. Nevertheless, this conflict has led to an extraordinary number of noncombatants suffering: one estimates suggests that over 3 million people in the area need food aid. These are black Africans fleeing their homes from attacks by Arab militias; however the UN does not consider this genocide.
The number of people who have died from starvation as a result of this conflict is staggering; unfortunately I wasn't able to find combat statistics to compare it too. It seems obvious, though, that the ramifications of this conflict are dire: even those who flee the area are still in danger, and the conflict may well follow them out of the country.