Stephen Walt, a vigorous and knowledgeable critic of U.S. policy toward Israel, has called for special envoy George Mitchell to resign his post.Walt begins his comments by arguing that Mitchell should get out while he retains his sterling reputation as a peacemaker -- not necessarily a good or noble reason for Mitchell to take heed. But in the course of a column posted on his blog, Walt gets down to a serious criticism of the current (and perhaps eternal) impasse."As for Mitchell himself, he should resign because it should be clear to him that he was hired under false pretenses. He undoubtedly believed Obama when the president said he was genuinely committed to achieving Israel-Palestinian peace in his first term. Obama probably promised to back him up, and his actions up to the Cairo speech made it look like he meant it. But his [Obama's] performance ever since has exposed him as another U.S. president who is unwilling to do what everyone knows it will take to achieve a just peace. Mitchell has been reduced to the same hapless role that Condoleezza Rice played in the latter stages of the Bush administration -- engaged in endless 'talks' and inconclusive haggling over trivialities -- and he ought to be furious at having been hung out to dry in this fashion."Hard words. Any reason for a true peacemaker to give up?http://walt.foreignpolicy.com/posts/2010/01/22/time_for_george_mitchell_to_resign