In his Jerusalem Diary on the BBC website, Tim Franks writes about the different languages spoken in Jerusalem and whether it helps if opposing parties speak each other’s language.

The question is how far those people within Jerusalem, and more broadly within Israel and the Occupied Territories, want to speak each other’s languages.
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“Let’s think of Northern Ireland,” Prof Spolsky told me. “They spoke English on both sides. That didn’t make them friendly. Language follows rather than leads. It’s sad. I’m someone who encourages language-learning. But being able to speak someone’s language doesn’t make you like them.”