[Benny Morris is a professor of history in the Middle East Studies Department of Ben-Gurion University of the Negev. His most recent book is One State, Two States: Resolving the Israel/Palestine Conflict (Yale University Press, 2009).]

Forget Osama bin Laden, forget the security fence between Gaza and Israel, forget—for a moment—the bomb-bound crazies in Iran. Sudan is the place to watch, probably the next combat zone in the ongoing clash of civilizations.

For decades the Christian and animist inhabitants of the southern half of Africa's largest state (two and a half million square kilometers—roughly one hundred times the size of New Hampshire) have sought liberation from the Muslim Arab dictators ruling from Khartoum. In the sporadic civil war they have waged, on and off, for the past fifty years one-to-two million people have died, overwhelmingly southerners, as the north's tanks and jets have shelled and bombed and depopulated their villages.

Now they want out, and on January 9, 2011, following the agreement signed in 2005, the southerners will go to the polls and vote in a referendum on Sudan's territorial integrity. All commentators agree that the vote, if it actually takes place and if fairly counted, will overwhelmingly favor secession.

How will the north react?..