What Obama faces in the Middle East, if he is to move the peace process forward, is a very powerful force against him. It's called AIPAC:

“I don’t think anybody wants to dictate to an ally what they have to do in their own national security interests,” said Rep. Gary Ackerman (D-N.Y.), who said he thinks there’s “room for compromise.” “I have to hear specifically from the administration exactly how they define their terms and is there room for defining the terms,” he said, referring to the terms “settlement” and “natural growth.” ... The pro-Israel lobby AIPAC last week got the signatures of 329 members of Congress, including key figures in both parties, on a letter calling on the administration to work “closely and privately” with Israel in contrast to the current public pressure.
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