Those Islamic people are actually tame by Wahabbi standards. They despise the U. S. When there is no king to hold them back, look out.
they would start fighting each other.
Let's look at the following maps
First, the dispersal of Sunnis and Shias and the various groupings of them
25% of Saudi citizens are Shia - twelvers or Zayyidi or Ismaili
- Now the twelvers Shias (who ay the fist twelve Imams, including the first 4 Sunni Caliphs) were good guys are the majority in Iran, but are not the same as the Ismailis or Zayyidis
- Zayyidis are closer to the Hanafi school of Sunni islam than they are to Twelvers -- they are called Houthis now by the Western Media
- ismailies follow the Aga Khan and are related to Bohris and Syedni Bohris -- the latter have their own heriditary Syedni leading them.
Now the Twelvers are the majority in the oil based provinces. And the Ismailis despise the Saudis for having bulldozed the graves of the early Caliphs and of Mohammad's wife Aisha -- they even wanted to destroy the grave of Mohammad. This also pissed off the Sufi school of Sunnis -- these revere "saints" -- whose tombs were destroyed by Wahabbis
you overlay this with the various tribes and clans etc.
And you see that the arabs would be just as they were before Lawrence of Arabia came and united them (remembe the movie when lawrence says "if the Arabs do not unite they will always be a divided and weak people")
So, DoughtyOne, if there is no Saudi king, expect a group of various emirates springing up -- some Sunni hanafi, some Sunni Wahabbi, sone Sufi-Sunni, Some Ismaili, some zayyidi, some Twelver shia and even some Ibadi in the east (or they would join with Oman)