But the US is intervening in syria on the side of the "rebels" who want to overthrow the Assad regime not the other way round whilst backing the bahraini government and the Saudi forces that came to the rescue of the Bahraini royal family against the democracy protesters in bahrain. A clear example of which countries are and are not US client states if ever there was one. Also have you anything to say on the Arab oil producing countries who could threaten to cut off oil production and supply to the "west" to help the Palestinians?
It's a clear example of realpolitik.
Assad is a brutal dictator and his people are trying to overthrow him. The US is generally supportive of democracy movements and is considering supporting them.
In Bahrain, there is a dictator (the King) who was not thought to be brutal until recently. There were protests by the Shi'ite majority in favour of more equality and perhaps some democratic reforms. The US did little to support them because Bahaini oil is quite important. I don't know how that makes them a client state. If anything they are dictating terms to the West.
The oil producing countries will not cut off oil to the West over Israel because they do not care about Palestinians. The vast oil wealth allows them to buy off their populace and continue their medieval style of government. They aren't going to risk that over people that they do not like very much.