The story: Supporters of Shiite cleric and politician Muqtada Al-Sadr have stormed Iraq’s parliament, only leaving after their leader’s call for their withdrawal. The protests erupted over the Iran-backed Shiite Coordination Framework’s push for Muhammad Shia’ Al-Sudani as its candidate for prime minister. In a show of defiance, ex-premier Nouri Al-Maliki (2006-14)—a nemesis of the Sadrists and a former associate of Sudani—was hours after the protests pictured holding a rifle on a street in the Iraqi capital. This comes as the commander of Iran’s Quds Force is reportedly in Baghdad to help contain the escalating tensions between Maliki and Sadr.

The political backdrop: The Iraqi constitution stipulates that two-thirds of Iraq’s 329-member parliament must be present for a quorum to be met and for the president to be elected. The president is tasked with charging the prime minister-designate of the largest bloc with forming the next government...