A Review of US National Security Strategies in the 21st Century (with Emphasis on the Trump Administration)

This article will discuss and compare The United States national security strategies over the past two decades. With focusing on three general considerations of "problem definition," "goals," and "approaches" in US national security strategies, the authors believe that there is a significant link between the Bush administration and the Obama administration national security strategies especially in definition of national security goals. This is also correct about foreign policy instruments (such as the alliances, coalition-building and multilateralism) exception the pre-emptive war, of course.  The remarkable difference between of them is about the relative importance of international order. During the Trump administration the language of problem definition, goals and tools has changed significantly. In light of the principled realism and sovereignty of the nations, the Trump’s NSS reflects a significant difference and emphasizes on the America First strategy, protectionism, reject the international responsibilities, diminishing military commitments and unilateralism.