Abstract
This study examines the role of international law and diplomacy in interstate relations, with implications for American-Afghanistan relations. Specifically, the study sets out to interrogate whether US war relations on terror in Afghanistan has reduced terrorism in the country; ascertain how US counter-terrorism strategic relations in Afghanistan undermined jus in bello principles of proportionality and discrimination; and determine how US strategy failure in its Afghanistan’s relations undermined its reconstruction and peace-building efforts. By adopting the Just War Theory (JWT), the paper analysed the dynamic nature of US-Afghanistan relations, following the 9/11 attacks, with findings revealing that the US had an incoherent strategy in its war relations in Afghanistan, which ultimately led to its failure to restore peace, promote democracy and human rights.