There are legitimate disagreements over settlements and Israel’s friends are entitled to criticise its policies, just as Israel is entitled to insist that its security requirements and historic and legal claims cannot simply be wished away. A trade ban, however, would not constitute constructive diplomacy but would mark another stage in Britain’s transformation from a candid ally into an increasingly hostile and unreliable one. The strategic cost to Britain itself would extend far beyond the trade directly affected. Israel is one of the world’s most advanced centres of innovation, particularly in cyber security, artificial intelligence, medicine, water technology and defence...