"Sunni Arabs are a minority in Iraq, but for many years they enjoyed a privileged status. This was especially so during the cruel and paranoid rule of Saddam Hussein, who reserved an outsize share of lucrative government jobs, powerful army commands and professional positions for Sunni kinsmen. The Shiite majority, along with the Kurdish minority, were subjected to relentless deprivation and violent, systematic terror.
The Shiite-dominated governments that have followed since the 2003 American invasion have been determined to redress that imbalance. They have gone too far — marginalizing and discriminating against the Sunnis. And in the early years, Washington did almost nothing to restrain them. The civil war that nearly tore Iraq apart in 2006 and 2007 has receded, but the resentments have not.
In recent weeks, Sunni extremists have begun a new campaign of bloody attacks on Shiite mosques and civilians, looking to reignite sectarian warfare as American forces ratchet back their combat role. To their credit, Sunni political leaders have condemned these attacks, and Shiites have, thus far, refused to be provoked. But the unresolved tension between the two groups is a problem that Washington cannot ignore."