The transfer of sophisticated military hardware from the United States to foreign nations is governed by a dense and multifaceted legal framework designed to balance the competing imperatives of foreign policy, national security, and international stability. This architecture is not merely a set of administrative hurdles; it is a deliberate system intended to ensure that U.S.-origin defense articles are used in a manner consistent with American interests and values. At the heart of this system lies the Arms Export Control Act (AECA), a foundational piece of legislation that provides the authority and the guiding principles for all U.S. defense trade. Understanding this statutory bedrock is essential to comprehending the stringent conditions, such as End-Use Monitoring (EUM), that are attached to the transfer of high-value assets like the F-16 fighter jet.¹