The dynamics of global peace and international relations are profoundly influenced by tariff regimes and principles of reciprocity in trade. This paper examines the multifaceted implications of these economic constructs on the geopolitical landscape, arguing that the evolution of tariff policies can serve as both a catalyst for cooperation and a source of conflict among nations. In an interconnected world, trade tariffs act as instruments of economic power, capable of shaping alliances and fostering dependencies, while also inciting tensions that may lead to trade wars and geopolitical strife. The reciprocity principle, which promotes mutual concessions in trade negotiations, is crucial in maintaining equilibrium and fostering trust between nations. However, disparities in economic strength and divergent national interests can complicate these interactions, potentially undermining peace efforts. Through a historical analysis of key tariff agreements and disputes, this study highlights how shifts in tariff regimes reflect broader geopolitical changes and impact international relations. The findings suggest that while strategic tariff implementation can enhance diplomatic ties and contribute to global stability, protectionism and retaliatory measures can exacerbate conflicts and undermine collaborative efforts. Ultimately, recognizing the interplay between tariff regimes and the principles of reciprocity is essential for policymakers striving to promote peace and foster beneficial international relations in an increasingly globalized economy. This analysis further delves into specific case studies where tariff regimes have played a critical role in shaping diplomatic relations, such as the U.S.-China trade relations and the implications of the European Union's Common External Tariff. Additionally, it explores how multilateral trade agreements and organizations, such as the World Trade Organization, function to mediate between national interests and foster cooperative trade relations that can mitigate conflict. This review paper explores the multifaceted relationship between tariff regimes, the principle of reciprocity in international trade, and their broader implications for global peace and international relations. By analyzing historical precedents, theoretical frameworks, and contemporary case studies, this paper reveals how economic instruments traditionally viewed through a domestic policy lens can significantly shape geopolitical stability and cooperation. The findings underscore the dual nature of trade policy, serving as both a catalyst for conflict and a platform for peace building.