We should carefully watch – but not interfere – as the various Middle Eastern religious/tribal/ethnic factions fight it out among themselves to determine which corrupt regime will next rob their country's treasury, at least until the next struggle. As we know, the defeated/expelled corrupt regime is usually killed off or, more recently, they head off en masse to the South of France and live out their lives anonymously with their purloined riches, sending their kids off to posh private schools in Switzerland. This seems the established Middle Eastern regime "leadership selection model" and it's probably not going to change anytime soon, at least as long as the oil (and opium) holds out to finance corruption, and the various local factions lust for the power and riches it brings them.
Saudi Arabia seems to be an exception to this practice, however, because they are basically a family rather than a country, to take a thought from the late Manachem Begin. As such, and because their politically operative numbers are so small, the royals are scared to death by the emerging political strength – and vast numbers – of the Muslim Brotherhood, and are therefore willing to spend whatever of their riches it takes to defeat them anywhere in their region.
Already, for example, the Saudis have promised billions to the Egyptian Army to help it put down the very well organized Brotherhood in that country, thus rendering moot whether the U.S. cuts off aid. Why? For the royal family, this is a life and death struggle for their future – and they know it. While perhaps ironically, our strategic interests are very nicely aligned with the Saudis – at least for now – and we should encourage them to help the Egyptian Army to reduce dramatically the Brotherhood's influence in the region.
All things considered, our fundamental national security interests are very basic in most of these struggles: Does the regime present a threat to us? And, if so, is it an urgent threat – or even a "clear and present danger?"
If the answer to these kinds of questions is "yes", we should – very seriously – explore the option of taking down the regime (or letting the Saudis pay to take down the regime) and letting another one take over – and, as they say in pest/weed control treatments "repeat as often as necessary".
Should we use U.S. ground forces? No – instead, we should, first, help the Saudis arm the various opposition regimes, as necessary and appropriate, and, if this doesn't do the trick, second, use our stand-off strategic weapons, drones, cruise missiles and the like, until the dangerous regime in question is neutralized. Or, in the Syrian example – at least until one or more of the various competing regimes are successful in their campaigns to take the Assad cabal down.
And we should continue to target precisely the various pretenders to Syrian leadership until there is one left that doesn't support terrorism against us. Also, in Syria, we must target precisely and destroy totally their chemical weapon capability/infrastructure and not allow it to be reconstituted under any successor regime. If we don't, someday and somewhere, someone will use these weapons on us – it's a matter of when, not whether.
The closest we have come to adopting this policy was the "lead from behind" effort to help topple the Gadhafi regime in Libya. However, and as evidenced by the terrorist attack in Benghazi on the anniversary of 9/11, we haven't – yet – gotten our policy "message" across to the successor regime(s) in Libya. Gadhafi's successors should be subject to the same personal threat he was – until and unless they reduce/eliminate/control their radical threat to us.
This kind of policy is unambiguous and simple to understand; it focuses on the nature and extent of the direct threat to the United States posed by one or another corrupt and radical regime in the Middle East. The regimes that sponsor terror against us should be taken down as efficiently – and cheaply – as possible, without risking the lives of American "boots on the ground."