 Welcome to the final week of this course and thank you for having been with us all along. And the course ends where it actually began, that is with issues of war and peace, as you may recall that the historical foundation of modern international law is usually traced back to the peace of Westphalia, which put an end to the Thirty Years War. And it is often when addressing issues of war and peace that international law enters the territory where its own existence is put in doubt. International law is a promise of peace and coexistence between nations of the world, but that promise, as you know, has been so many times disappointingly not kept, that doubts abound about the effectiveness of international law. War and peace are the twilight zone of international law. Before addressing the rules relating to international peace and security, let me say a few words about the incestuous relationship between violence and law. The relationship between violence and law can indeed be called incestuous, because if law reflects a certain ordering of social life and therefore a certain equilibrium between social forces, there is no social order through law without a certain degree of legitimate violence. And by this I simply mean that law, which is the opposite of violence, must nevertheless and ultimately rest on some form of coercion in order to preserve effectively the social order it reflects and protects. So viewing international law as a promise of a sugary world where the use of armed force would never occur anymore and where resorting to violence would always be wrong. Well this type of conception is antithetical to law itself. In other words, law can only regulate violence. By and of itself, law is not only incapable of completely removing violence from social relations, but more fundamentally it must to a certain degree rely on legitimate forms of violence to sustain itself. And this is true in domestic legal orders where violence is banned between citizens, but where the state apparatus has, through the police and the armed forces, the monopoly on the legitimate use of violence. And this is true also in international law. So instead of simply banning the use of force, international law should also contemplate what we all hate to contemplate that is resorting to war in order to protect the global social order. And as we shall see in this last part of the course, international law has developed some more or less clear substantial rules relating to the outlawry of war, and some procedural rules relating to the use of force in the name of the international community. But international law is still cruelly lacking a set of agreed, substantial rules that would help to take principled decisions when those procedural rules are set in motion. As we shall see, there is a procedure under which war can be made legal by the Security Council, but what are the wars that should be made legal that remains completely unclear from a normative point of view. Hence the Security Council procedure remains to a large extent a formal procedure devoid of any substantive values. And also when addressing issues of war and peace in international relations and law, it is impossible not to notice that if those issues are of course of interest to every state of the international community, well some states do not have the same military capabilities. Therefore, when states speak about war and peace and the rules relating to war and peace, states will always take into account their own strength or their own weaknesses. In other words, what states say about the rules relating to the use of force very much depends on their own military capabilities. And for instance, if one has to make a study about anticipatory self-defense and whether it exists under international law, it would not really come as a surprise that the views of the United States of America or the views of China on the issue are pretty different from those of, say, Liechtenstein. And despite the main principle of equal sovereignty between states, it is difficult not to take more into account the views of the US or China rather than the views of Liechtenstein when it comes to anticipatory self-defense. And this is just common sense. And law does not grow and prosper away from common sense. With that in mind, let me quickly tell you what's on the menu for this last week. We'll start with recalling the emergence of the rule prohibiting the use of force. When done so, we'll turn to the content and the scope of the prohibitive rule. And after that, we'll address the right of self-defense, be it individually exercised or collectively exercised, as an exception to the prohibition to use force. We'll pay a special attention to the use of force in self-defense against terrorist groups. In another section, we'll turn to the legal architecture of collective security under the UN Charter and we'll study the procedure by which wars can be made legal by the Security Council. Later, we'll see how those principles and procedures work in practice by addressing peacekeeping and peacemaking operations. We'll also question the Charter's rules in situations of humanitarian crisis when the collective security system has failed.