"The protesters aren't talking about Shiism or Sunnism ... their political language is about social justice ... democratic rights, and reform," says Toby Jones, a Middle East history professor at Rutgers University in New Jersey. "The way [the regime is] justifying a crackdown on these public protests ... is to say that this is a foreign plot."
That approach plays on the Saudi-Iranian struggle for regional dominance that pits the rich Sunni kingdom against Iran's Shiite theocracy. Since the 1979 Iranian revolution, it has played out in everything from Iraq's civil war to Lebanese tensions between Sunni politicians and the militant Shiite Hezbollah group.
On March 14, Saudi troops entered Bahrain at its request to help put down the protest movement. Two days later, security forces cleared the main encampment in the capital. Since then, Shiites have been targeted by security forces at checkpoints and many have described being arrested, subjected to anti-Shiite slurs, and beaten.