The main responsibility to protect civilians lies obviously with States, but it is also clear that, in some cases, States need international support to carry out that responsibility. United Nations peacekeeping operations and United Nations missions, as well as United Nations agencies in general, are crucial to strengthening and helping national capacities to exercise that fundamental responsibility. We are aware that the very nature of armed conflicts has changed. Armed groups roam unchallenged within the borders of often vast countries, sowing violence and death, and avail themselves of the porosity of borders to further their criminal intentions. This new reality adds significantly to the complexity of the tasks of peacekeepers and strains their capacity to enforce compliance with international humanitarian law and uphold respect for fundamental human rights.