Sudanese government troops and southern Sudanese forces have led a tense coexistence for months in the oil-rich area of Abyei, which straddles Sudan's north and south. Accounts of what ignited the recent fighting (Economist) between the two groups differ, but no one disputes the end result: a town destroyed (WashPost), roughly one hundred thousand people displaced, and the probability of civil war on the rise with each passing day. Abyei exemplifies the most contentious elements of a 2005 peace deal between north and south Sudan. Analysts say the town's future is critical to the viability of that agreement, and by extension, prospects for a resolution to the crisis in Darfur.

The 2005 Comprehensive Peace Agreement that ended a decades-long civil war between north and south Sudan includes a separate protocol for Abyei. Both sides claim the area, which grossed about $670 million in oil revenues in 2006. A portion of the area's oil revenue is supposed to go directly to residents of Abyei, but there were concerns at the time of the agreement about how the money was being shared. The Abyei protocol gives the area a special administrative status, delineates a process to determine its boundaries, and calls for a referendum in 2011 to determine if the area will be part of the north or the south. That referendum is scheduled to coincide with a referendum on whether south Sudan will secede from the north. Experts say Sudan's ruling National Congress Party seeks to avoid secession at all costs, but it is also trying to arrange the north-south border so that it retains as many oilfields as possible in the north.

The turmoil in Abyei comes at a time of shifting U.S. policy toward Sudan. According to the State Department, U.S. policy emphasizes ending the violence in Darfur, providing humanitarian assistance, and pushing for full implementation of the Comprehensive Peace Agreement (CPA). There has been little movement on these points in recent months, yet there are signs Washington is pursuing normalization talks with Sudan, which remains on the state sponsors of terror list. U.S. Special Envoy Richard Williamson plans to meet with Sudanese President Omar al-Bashir in the next several weeks (WashPost). Though some experts advocate such engagement, human rights groups and some policymakers criticize Washington for not taking a harder line.

Other experts say the United States has focused its Sudan policy on Darfur to the detriment of the north-south agreement. For the past three years, U.S. policy toward Sudan has focused on the crisis in Darfur, where clashes between Arab janjaweed militias and Darfur rebel groups have displaced millions and left hundreds of thousands dead. While the United States has pressed for the deployment of a robust peacekeeping force to the region, regional analysts are calling for more U.S. attention on seeing through implementation of the CPA. In fact, Khartoum has played Darfur and the north-south conflict against one another (PDF), argues a report from the Center for America Progress' ENOUGH project. "International policies must no longer be bifurcated between the CPA and Darfur," warns the International Crisis Group. "Sudan's multiple conflicts are outgrowths of a common set of national problems and need to be treated as such."

Much will depend on the willingness of the National Congress Party and the Sudan People's Liberation Movement (SPLM), the dominant party of south Sudan, to negotiate. The SPLM suspended its participation in talks with Khartoum and the United States this week, citing the recent violence in Abyei (VOA). Though experts say the National Congress Party is skilled at survival, some see signs of weakness. Andrew Natsios, former U.S. special envoy to Sudan, writes in a recent Foreign Affairs essay that the ruling party has developed a "siege mentality." If fighting escalates between the north and south, he writes, "the war would come to Khartoum very quickly."