Remarks by French President Emmanuel Macron that he wanted to repair church-state ties caused uproar Tuesday, sparking charges he was tampering with France’s longstanding secular tradition. The Church and the state were for centuries virtually indistinguishable in France, but the 1789 Revolution marked the first step by republicans to exclude religion from government affairs, codified in a 1905 law separating the two. But tensions have persisted, with conservative politicians often accusing officials of denying France’s cultural heritage — as seen in efforts to install nativity scenes at town halls during Christmas. Macron, who prides himself on tackling difficult issues head-on,...