After two world wars, states divided by ideology nonetheless built a common international order. Faced now with the dangers of climate change, AI and rising militarism, they must find ways to cooperate again.

Since Russia invaded Ukraine, Germany has broken with its postwar military restraint: it is rearming at speed and has set its sights on becoming NATO's leading European power, with US blessing.

There are regular warnings that France risks succumbing to fascism. But Mussolini's Italy may not be the model that attracts the far right; it could be Binyamin Netanyahu's de facto apartheid state.