The events in Darfur were first and foremost a Civil War, even if their consequences included a major humanitarian crisis.  Darfur rose in rebellion against the central government first, and even the local conflict was a civil war, the Abbala tribe from which the janjaweed are drawn has a long history of conflict with settled Darfur tribes, which drove them off their land centuries ago.  That the death toll in these conflicts was raised by the introduction of modern armaments is clear. What is not clear is how Western intervention would have solved either the underlying problems, or created a deterrent. The most likely outcome would have been genocide of the Abbala, as the West already demonstrated in Kosovo that it is unable to protect the “perpetrators” of genocide from its “victims” even with large military forces present.