Were I a Palestinian, I would appeal for a relatively neutral third party to arbitrate blame. USA cannot be objective, and while Israel probably does not see Obama as being as pro-Israel (or at least not as likely to accede to Israeli wishes running contrary to peace) as previous administrations, the Palestinians should see USA as still heavily slanted toward Israel (in other words, the most Israel-aligned nation on the face of the Earth). I would rather see a "blame jury" panel of 5-9 neutral-ish Far East or South Pacific island states decide who is to blame. Of course, they'd be deciding shades of gray, not pure black and white.
U.S. Senate blocks Republican move to defund Planned Parenthood (Reuters)
from the article: Exclusive: U.S. vows to assign blame if Israel-PA talks fail