To mark the 20th anniversary of the 9/11 terrorist attacks in fall 2021, this seminar will engage students in a critical assessment of the impacts of those attacks and their aftermath on a range of areas of international law. These areas include the international law on terrorism, on the treatment of victims of terrorism, on the use of force, on human rights, on fundamentalism and extremism, and on the principle of non-discrimination. Particular attention will be paid to the situation in Afghanistan in light of the planned U.S. withdrawal on the twentieth anniversary of 9/11, and the human rights situation on the ground in the country. How did 9/11 and the responses to it change international law? What can or should be done about these consequences today?