Seems to me that comprehension really isn't a requirement on her part, anyway.
As for the rhetorec in terms of the Israel issue, it works like this:
Arab strategists create rhetorec tailored to leftist sensibilities, seizing upon framing techiques in such a way as to either draw parallels to issues the left is known to support or else to achieve an emotional reaction via the specific choice of words (such as "apartheid", etc) . This rhetorec is intellectualized by the likes of Noam Chomsky whereupon it is channeled through Universities and repeated by the various Juan Coles and Ward Churchills, or else simplified into buzz phrases and channeled through various terrorist support groups like the ISM and the PSM. These "solidarity" groups overlap considerably with groups such as the Socialist Workers Party, International A.N.S.W.E.R. and an umbrella group called "United For Peace and Justice".
The latter is most likely signifigant here, because Ms. Sheehan has been known to show up wearing UFPJ logos, and ANSWER is the biggest organizer within the antiwar movement. The demonization of Israel is just all part of the general program and repeated as dogma. Tough to say how much personal animosity she feels towards Jews, or how much of this rhetorec she really comprehends. It has become so de rigueur for the authoritarian left to spout this stuff that it's anybody's guess.
Oh, and to comment on the thread topic -- no, I would not vote for her.
Even if I were still living in the state where I have spent the majority of my life.