A few weeks ago, I posted here an explanation of Sunni and Shia Muslims, and recommended that this divide be kept in mind when analyzing events in the Middle East. Today, that divide is on display in Yemen.
Saudi and allied warplanes struck rebels in Yemen on Thursday, with Saudi Arabia threatening to send ground troops and inserting itself into its southern neighbor's civil war, potentially opening up a broader sectarian conflict in the Middle East.
The swift and sudden action involved 100 Saudi jets, 30 from the United Arab Emirates, 15 each from Kuwait and Bahrain, 10 from Qatar, and a handful from Jordan, Morocco and Sudan, plus naval help from Pakistan and Egypt, according to a Saudi adviser.
What do those countries have in common? They're all predominantly Sunni Muslim -- in contrast to the Houthi rebels, Shiite Muslims who have taken over Yemen's capital of Sanaa and on Wednesday captured parts of its second-largest city, Aden. The Saudis consider the Houthis proxies for the Shiite government of Iran and fear another Shiite-dominated state in the region.
The second map shows in green the area of Yemen controlled by the Shia faction, called the Houhtis.