This chapter examines the intricate relationship between economic sovereignty, economic nationalism, and trade wars, establishing a comprehensive theoretical framework to analyze contemporary international economic conflicts. It applies this framework specifically to the US-China trade war, arguing that the rivalry is a deep, multi-layered phenomenon that cannot be understood through superficial economic indicators alone. The chapter begins by tracing the historical origins and modern transformations of economic sovereignty, demonstrating how globalization has reshaped, rather than eroded, the concept by adding new dimensions like technological and digital sovereignty. It then delves into economic nationalism as the primary ideological force driving this quest for sovereignty, citing policies like the US's "America First" and China's "Chinese Dream" as prominent examples, while also presenting a critical evaluation of the potential inefficiencies and risks associated with such policies.

A central focus of the chapter is its analysis of trade wars through two distinct International Relations theories. The Realist perspective is used to frame the US-China conflict as a classic power struggle for relative gains between a hegemonic power and a rising challenger. In contrast, the Constructivist perspective is employed to illuminate how this struggle is socially constructed—examining the creation of "threat" perceptions, the discourse of "unfair competition," and the central role of national identities and normative claims in legitimizing protectionist actions. The chapter concludes that the US-China trade war is a quintessential manifestation of resurgent 21st-century economic nationalism and a transformed understanding of sovereignty, a conflict that is testing the foundations of the liberal international order and has the potential to reshape the future of the global trade regime.