SAUDI ARABIA

The simultaneous bombings of Shia mosques in Yemen and Saudi Arabia claimed by Islamic State are a spillover of Riyadh’s Yemeni adventure and a warning  that the jihadists have the kingdom in their crosshairs. With IS advancing in Syria and Iraq, Riyadh faces threats on several fronts.

Islamic State (IS) has in recent weeks expanded its presence in Syria, where it controls more than half of the country’s territory, while its capture of Ramadi in Iraq’s...