美国“印太战略”新布局：“第四岛链”

Core Viewpoint - The recent deployment of B-52 bombers by the U.S. to Diego Garcia has sparked significant attention, highlighting the U.S. strategy to strengthen its military presence in the Indo-Pacific region and the development of a "fourth island chain" to counter China's influence [1][9]. Historical Context of the "Island Chain Strategy" - The "island chain" strategy originated during the Cold War, with the U.S. initially proposing the "Eastern Arc" to contain the Soviet Union [2][3]. - In the 1950s, U.S. officials defined defense lines in the Pacific, establishing a series of island chains to create a military blockade against the Soviet threat [2][6]. Current Strategic Developments - Following the dissolution of the Soviet Union, the U.S. has adapted the "island chain" concept to address the rising influence of China, viewing it as a primary competitor [6][9]. - The U.S. has established three primary island chains in the Pacific to contain China: the first chain includes key islands from Japan to the Philippines, the second chain extends from Japan to Indonesia, and the third chain centers around Hawaii [8][9]. The Concept of the "Fourth Island Chain" - The U.S. is exploring the creation of a "fourth island chain" that would extend from Pakistan's Gwadar Port through Sri Lanka to Diego Garcia, aiming to transform the Indian Ocean into a controlled area against China [11][14]. - This new chain is strategically designed to control critical maritime routes and counter China's Belt and Road Initiative [14][15]. Key Locations in the "Fourth Island Chain" - Gwadar Port: A crucial point for China, located at a strategic maritime junction, which the U.S. aims to monitor and restrict access to [13][14]. - Hambantota Port: A significant hub for global shipping, which the U.S. seeks to undermine China's influence over [15][16]. - Diego Garcia: A vital U.S. military base in the Indian Ocean, providing logistical support and strategic reach across multiple regions [16][19]. Challenges to Implementation - The realization of the "fourth island chain" faces significant challenges, including the complexity of geopolitical relationships in the Indian Ocean and the limited military resources available to the U.S. in the region [20][21]. - The existing Chinese presence in Gwadar and Hambantota complicates U.S. efforts to exert control over these strategic locations [21].