چکیده:
The formulation of U.S. national and regional security in the 21st century is a function of the power equation and geopolitical shifts within the international system; this dynamic remains consistently influenced by changes in the orientation of the hegemonic and system-structuring power. Alterations in the balance of power leave their impact on the trajectory of regional competitions among actors, including the United States. U.S. security policy in the 21st century has led to the emergence of intractable crises. The primary research question of this study is: "What impact have U.S. regional security strategies in the 21st century exerted on international politics and regional order?" Furthermore, the research is grounded in the hypothesis that "the security strategy and functions of the United States in the 21st century—which encompass an evolutionary trajectory from acute unilateralism (preemptive war) to regional multilateralism—have established the groundwork for crises in international politics." Data analysis was conducted using the fundamental analysis method. Findings reveal that while the Bush and Obama administrations differed in their general definition of threats and challenges facing the United States, they largely concurred regarding national security objectives; their fundamental divergence lay in the relative importance accorded to international order. The national security strategies of Bush and Obama concerning foreign policy tools and approaches were substantially similar (excluding preemptive war). Conversely, the Trump administration reconceptualized threat identification and reformulated objectives and approaches, adopting a "self-reliance" strategy aimed at achieving the "America First" slogan. Collectively, although evolution is observable in U.S. foreign policy, its outcomes—manifest as crises across various regions—have remained unchanged.
خلاصه ماشینی:
200 Supreme Politics, Vol. 13, No. 49, 2025 Examining the Role of US Security Policy in the 21st Century and Global Security Crises 1 3 Hamid Jahangiri 1, Fakhruddin Soltany 2, Armin Amini 1 PhD student, Department of International Relations, Karaj Branch, Islamic Azad University, Karaj, Iran.
Furthermore, the research is based on the hypothesis that US security strategies and functions in the 21st century, which evolve from acute unilateralism (preemptive war) to regional multilateralism, have provided the grounds for creating crises in international politics.
In this process, Barack Obama put the policy of maximizing allies on the agenda, Trump implemented the strategy of reducing geopolitical costs, and Biden adopted the policy of geopolitical changes based on strategic multilateralism and offshore balancing.
Examining US national security documents indicates that signs of change are a function of structural necessities in each historical era, and signs of tactical complementarity can be observed in the behavior of US foreign policy (US NSS, 1987).
He proposed a strategy that re-presented the primary national interests of the United States in a similar format Examining the role of US security policy in the 21st century and...
The important point is that the research and examination of the security functions and foreign policy of the United States during the Trump era is significantly different and, consequently, more difficult than previous administrations.
The first sign of the change in Trump's national security doctrine and foreign policy compared to the Obama administration is a different structural view regarding the category and issue of threat.
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