This came right on the heels of a U.A.E. court sentencing Qatari doctor Mahmoud al-Jaidah to seven years in prison on Monday, for the crime of aiding a banned opposition group called al-Islah, which the U.A.E. government alleges has operational ties to the Muslim Brotherhood.

This was a coordinated move, led by the Saudis, to punish Qatar for supporting Muslim Brotherhood interests around the Middle East (and also for assuming a more prominent role in pan-Arab politics in general), but beyond that it reflects the Saudis’ deep and ongoing concern about an Iranian resurgence in the Gulf.

From the Saudi perspective the Qataris have been punching above their proper weight, and making nice with the wrong people.

Qatar’s ties to the Muslim Brotherhood are clearly the public justification for this row; it is no mystery why Saudi Arabia followed up Wednesday’s diplomatic swipe at Qatar with a decision on Friday to declare the Muslim Brotherhood a terrorist organization.