 From a legal point of view, the interwar period was marked by another turning point, which added to the League of Nations' rules limiting the freedom of states to resort to the use of force to settle their disputes, rules, however, that did not completely outlaw war as an instrument of national policy. What was called then the outlawry of war was achieved by the Treaty of Paris of 1928, which is also called the Brian Kellogg Pact, as it was a joint idea of the French and the American foreign affairs ministers. About ten years later, however, international law bitterly proved its limits again. Poland was invaded by Nazi Germany on 1 September 1939, and Eastern Poland was invaded two weeks later by the Soviet Union. The Second World War began. It ended with a total victory over Germany, its occupation and division, as well as the division of Europe. Detached from any peace treaty, the Charter of the United Nations was signed in San Francisco on 26 June 1945, with, as the first sentence of the preamble emphatically stresses, with the determination and the very noble ambition, I quote, to save succeeding generations from the scourge of war, which twice in our lifetime has brought untold sorrow to mankind. End of quote. War with Germany had ended on 8 May 1945, but war with Japan was still raging, only to end with the atomic bombs dropped on the cities of Hiroshima and Nagasaki on 6 and 9 August 1945. As I recalled earlier, the UN Charter continues to be based on the principle of equal sovereignty of states. Quickly after the Second World War, the Cold War divided the great victorious powers and paralyzed the United Nations to a large extent. However, during the late 1950s and throughout the 60s, one major achievement of the UN was to foster the decolonization of Asia and Africa. A new principle of international law emerged, and it radically changed the face and the agenda of the international community. It is the right of peoples to self-determination, understood as the right of European colonies to become independent. But then again, and despite the revolutionary aspect of the right to self-determination, the basic structure of international law did not change. Colonies wanted to become what their former masters were. They wanted to become states. The fundamental paradigm of international law remained the equal sovereignty of states. In many places around the world, the decolonization was a bloody and messy process, not only because some colonial powers were fiercely reluctant to relinquish their domination, but also because it allowed for the East and the West to fight wars by proxy in order to try to attract within their respective spheres of influence the newly born states. And then came some years of detente during which Washington and Moscow tried to accommodate their deep differences and eventually also to limit their respective arsenals. With the liberation of Nelson Mandela in February 1990, with the reunification of Germany a few months later, and with the collapse of the Soviet Union in 1991, the Cold War gradually came to an end, and it opened an intensive era of cooperation between states. When Iraq invaded Kuwait in August 1990, the UN Security Council stood together and acted jointly, proving a new resolve and opening a new era for the revival of the UN and for the development of international law. But international law was not only a matter of peace and security in the narrow sense of the world. Three fundamental issues, development, human rights and the protection of the environment, those three new issues created a new sense of interdependence between the nations of the world, gave new dimensions to the notion of peace and security and directly challenged the paradigm of state sovereignty on which international law had been so far built and which international law had protected. The last decade of the 20th century saw the creation for instance of the World Trade Organization, of the Yugoslav and Rwandan international criminal tribunals, of the International Criminal Court, of the Organization for the Protection of the Prohibition of Chemical Weapons, so also the creation of the Kyoto Protocol on climate change, it saw also the Rio Summit on Sustainable Development and the establishment of many peacekeeping operations around the world, just to name a few institutions and a few instruments that are based on the fundamental idea that coexistence and cooperation between nations are best served and achieved through the development of international law. And at the same time, that sovereignty must be transcended in order to adequately address common challenges. So despite terrible failures like the genocide in Srebrenica and in Rwanda, the end of the 20th century was marked by a deep sense of multilateralism and common purpose. The development of TV networks, of the internet, telecommunications and social media, together with a growing air transport industry and the expansion of international trade, all that provided for a new era of globalization. Well true, the United States of America established itself as the only superpower, but it was largely seen as a benevolent superpower, a power which was positively engaged with the rest of the world and which strived with the rest of the world to improve it. And all that suddenly came to an end with the terror attacks of 9-11 and even more with the invasion of Iraq in March 2003 by the U.S. and U.K. forces. Multilateralism came to a halt and was replaced by unilateralism, sometimes clothed in so-called coalitions of the willing. But coalitions also proved to have limits and more problems arose. Coexistence come and go while institutions are resilient and their international law instruments remain. It is of course too soon to tell and nobody can read in the future, but despite its pitfall and its limits international law remains one if not the only viable tool that can provide legitimacy for action in the world and foster coexistence and cooperation between states. Coexistence and cooperation. That is what international law is fundamentally about. Coexistence and cooperation may sound very modest purposes compared to a prophetic agenda of peace and justice in the world, but what a difference coexistence and cooperation make and how essential they are in the pursuit of those higher ideals.