It's less of a crime first of all because the UN is the closest thing we have to a world legislative body, and as such it is the most relevant arbiter of what constitutes an international crime or not.

Secondly, the Israeli occupation of the West Bank does not allow for sufficient Palestinian participation or for sufficient respect for Palestinian community and economic rights. The UN, imho, stands a much better chance of providing greater opportunities for Palestinian self-government and participation, as well as having greater legitimacy in the eyes of Palestinians.

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it is a mistake to throw out the language of equal worth because of its contingent historical association with Western power.