Really, you can't really blame Obama for operating when the US political establishment. This is called the "reality principle." He is president of the US and has to function in its political/societal/cultural milieu. Duh. I mean, it is politically impossible for a US president to advocate some of the policies people think Obama should be advocating (like on Israel). Probably some people put unrealistic hopes in the guy, but that's their problem, not his. Sure he probably catered to it, but that's what politicians have to do.
I'm not a huge Obama fan, but some of this stuff is silly, as if when you became US president you suddenly obtained magic powers to do anything you wanted.