The competition for hegemony between China and the United States is expected to intensify over time. Even if the current trade war between these tow power concludes, similar types of conflict are likely to recure as long as the U.S-China hegemonic rivalry persists. Using an explanatory research method, this article examines the competition between the U.S and China through the lenses of hegemonic stability theory and power transition theory. The central question addressed is: what happens when an established power and an emerging state confront one another in global politics? The hypothesis proposed is that the outcome depends largely on the strategic choices of the established power toward the emerging power. The practice, American fear of its declining hegemony and the rapid rise of China as a rival has driven the strategic choices of U.S leaders- from Obama to Trump and Biden- ranging from competition and trade wars to occasional compromise. The findings indicate that the root cause of the rivalry and trade war between the world's two largest economies is primarily political: specifically, a struggle for global hegemony. Consequently, the United States does not impose tariffs on Chinese goods merely to improve its trade balance rather.it seeks to contain and manage China to preserve its own global dominance. Therefore, a comprehensive understanding of the U.S -China trade war requires careful attention to the significance of the power competition between these two nations