For months, Israel’s staunchest allies in the U.S. and Europe had largely avoided using the C-word. To call for a ceasefire, they argued, would be to deny Israel its right to root out Hamas from Gaza in retaliation for its Oct. 7 massacre. But as the humanitarian situation in the Strip has deteriorated and as calls for an end to the hostilities have grown, pressure has mounted on Israel and its backers to change tack.