Another problem is that the Eastern Province, primarily just north of Bahrain up to Kuwait is predominantly Shiite. Near the middle of this stretch of land is Rastunara, the oil export port and the largest oil refinery in world. The Shiites that live here are treated like second class citizens and are actually regarded as infidels. If they join forces with the majority Shiite population of Bahrain with the assistance of Iran, it is conceivable that they could take over the Eastern Province (where most of the oil is).
Iraq is majority Shiite and would be a push over when US leaves. Syria is already being controlled by Iran. Hezbolla which is just a proxie organization controlled by Iran, which is slowly taking over Lebanon. In the first Gulf war Yemen sided with Saddam against Saudi. I would appear that Iran is tightening their grip on Saudi. Ironically their best friends in the region are probably Israel.
