The stick has to be paid too--otherwise things don't go very well for those who wield it. Saddam at least had enough of a domestic economy to tax to pay for the security services, as well as a loyal extended family that actually did some of the grunt work, whereas it is doubtful the Saudis have either.

> If the carrot does not work anymore, they have the stick.

Not really; while they've spent a lot of money of hardware to use as the stick, they House of Saud lacks the loyalty of enough of the population for the stick to be the primary control -- they need a lot of carrot to even keep the trigger fingers that would apply the stick on their side, which is a lot of the reason for all the accommodation the regime makes with religious extremists.