The war in Ukraine is not only destroying citizens and cities, its consequences on the world are much wider. It leads to the emergence of a potential serious food crisis affecting mainly the least developed countries already suffering. Far from the peace promised by free trade, it highlights the latent conflicts between States and multinational firms, the fragility of the development of renewable energies in a context of energy war, the emergence of national stagflation fought by protectionist or even mercantilist policies for the greatest powers. It even seems to herald the end of the "post-cold war" era towards a new period that will be shaken by crises and the choices that States will have to make between the desire to maintain a market economy open to the world, the need to fight global warming, the search for economic growth based on nationally controlled technologies and the choices of partnership to be made with the two great powers, the United States and China, who are in conflict over world leadership. Finally, the solutions to the war in Ukraine remain diplomatic, unless we risk the emergence of a world war.