After a few years of stormy transalpine relations, Italy and France are putting their differences behind them with a treaty that is meant to establish a new motor of cooperation between two EU heavyweights in sectors ranging from industry to culture. In a sign of the importance of the rapprochement, Italy is taking the highly symbolic step of hosting Friday’s ceremony — and a dinner the night before — in the president’s sumptuous Quirinale palace, under the gaze of helmeted cuirassiers. In testament to the long roller-coaster ride of Franco-Italian tensions, the former papal palace chosen for the event was redesigned under the instructions of Napoleon who had planned to turn it into his residence after French forces occupied Rome, although he never ultimately moved in.