It was NOT a straight across the board 'carte blanche' for Israel to keep all its settlements blocks. It's talking about "mutually agreed changes" to the 1949 armistice line - give and take...NOT just take. ALSO, there's alot more to that letter, much of which YOU'RE ignoring when you accuse Obama of refusing to honor it...especially when in fact he's doing nothing that really contradicts it. Have you read the letter - or are you operating from hearsay?
Jerusalem light rail conductors striking over new train schedule (Haaretz)
from the article: Only the Bush-Sharon formula can save Obama and Netanyahu