This paper utilizes the K-Means algorithm in data mining to mine the changing trends in U.S. politics and economy, as well as the important nodes of U.S. diplomatic strategy towards the world. It explores the characteristics of the transmission mechanism of US economic policy, and the rise of small multilateral foreign policy partnerships. The mechanisms and paths of political polarization and economic recession in the United States, which affect the formulation of U.S. foreign policy towards the globe, are revealed. The study finds that the United States, under the dual impact of political polarization and economic recession, has shifted from a multilateral foreign policy practiced during the Cold War to a small multilateral foreign policy at the time point of 2017 (Trump’s administration). Through small multilateral diplomacy, the United States has strengthened the linkage between allies and partners in the region, improved the structure of cooperation, and promoted the integration of mutual interests. However, it has also indirectly led to the decline of the United States’ “unipolar hegemony”, the contraction of foreign strategy, the rapid decline of the leadership of multilateralism, and the gradual exposure of the endogenous contradictions between the Asia-Pacific strategy. Under the influence of Trump, the U.S. government has developed a more obvious institutional dependence on small multilateral diplomacy when formulating and advancing its foreign strategy, and the continuation of the small multilateral foreign policy can be found in the three years of the Biden administration.