No, capability. The largest "friendly" (read: Not Iranian) Middle East military is the Saudi. According to Wikipedia they have 192,000 troops and according to another source they have 233,000. If they committed 100% of their Army to the fight they still would fall short of the coalition forces that invaded Iraq in 2003, and that's not accounting for the woefully inadequate amount of personnel MNF-I had to conduct post-invasion operations. That's aside from the fact that they own territory in a volatile region and have to maintain the capability to defend their borders.
Officers of questionable loyalty and operational/tactical ability would also fall under the 'capability' category.
An invasion of the region by a Middle Eastern country would take a coalition effort, and these countries tend not to play nice with each other to begin with.