The Arab countries straddle the lifelines of world trade. They link Europe to Asia and, with Iran, surround the Persian Gulf home to some 54 percent of global oil reserves. The region’s many international and domestic disputes, as well as restraints on political expression and human rights, have spawned extremism. In turn, the region’s endemic instability or perceived risk of instability has provided cover for some of the world’s most authoritarian and corrupt regimes. Until the turn of this year, the Arab countries had almost uniformly resisted the process of democratization that swept up other regions in recent decades. The series of popular revolts known as the Arab Spring, which began in Tunisia in the last weeks of 2010, has already wrought more change in six months than the region had seen in almost 60 years and there is more to come. Whether or not the Arab peoples’ aspirations for dignity and voice are fulfilled, and how smoothly transitions to democracy proceed, are not just great moral questions they will also determine the region’s stability and its economic prospects for decades to come. At the same time, getting on a path of sound economic growth will greatly enhance the chances that transitions to democracy succeed.