The Persian Gulf: Rising Shia and Uneasy Sunnis

Hundreds of Shia clashed with riot police in Bahrain on Dec. 18 in the latest unrest in a series of such incidents this year. Meanwhile, Saudi authorities announced Dec. 18 that they are studying the grievances of the kingdom's Shiite minority. These events are a stark reminder to the Persian Gulf countries that, despite recent moves to engage Iran positively, Tehran's ability to influence their Shiite populations remains a serious threat to their internal stability.