This time by a bunch of academics:

The massacres in Gaza are the latest phase of a war that Israel has been waging against the people of Palestine for more than 60 years. The goal of this war has never changed: to use overwhelming military power to eradicate the Palestinians as a political force, one capable of resisting Israel’s ongoing appropriation of their land and resources. Israel’s war against the Palestinians has turned Gaza and the West Bank into a pair of gigantic political prisons. There is nothing symmetrical about this war in terms of principles, tactics or consequences. Israel is responsible for launching and intensifying it, and for ending the most recent lull in hostilities.

Petition text and list of signatories.