Anthony Housefather, an outspoken Jewish MP from Montreal, toyed with leaving his party to join the Conservatives after most of Trudeau’s Liberals voted in favor of a non-binding motion in the House of Commons that took direct aim at Israel. It’s the latest example of how the conflict is straining center-left politics across the globe — and challenging the place of Jewish leaders in mainstream progressive politics.

The progressive New Democratic Party had introduced a motion that called for the unilateral recognition of a Palestinian state and a suspension of arms trading with Israel. Dozens of Liberals were said to be supportive. Up against a divided caucus, Trudeau’s government negotiated softer language, including support for a two-state solution and a halt to “further authorization and transfer of arms” to Israel.