It was once remarked that Britain has no eternal allies and no perpetual enemies. But the 120-year anniversary of the Entente Cordiale, which reduced the near-isolation into which both powers had withdrawn, serves as a reminder that we may have something akin to a permanent friendship. In The Telegraph, Lord Cameron and the French minister for Europe and Foreign Affairs, Stéphane Séjourné, write of their commitment towards “renewing” the “essential unity of our interests and desires”.