造成这项转变的核心因素包括中国的崛起、数位革命以及右翼民粹主义的胜利。中国实施改革开放后成为美国百余年来首个实力相当的竞争对手，而数位技术则加速了全球化，同时带来了深远的社会与政治动荡。
如今，美国内部面临民主体制与法治被削弱的危机，外部世界则呈现民主倒退与地缘政治紧张，形势与1914年前极为相似。尽管核武器与对繁荣的追求降低了大国战争的机率，但气候变迁、人工智慧管理等共同挑战仍考验著人类的未来。
The United States rose as a global hegemon in the 20th century and reached the pinnacle of its influence, termed the "unipolar moment," after the end of the Cold War and the collapse of the Soviet Union. However, this hegemony did not last, and like the British Empire before it, the US role as a stabilizing global power has gradually waned over the past 35 years.
The core factors driving this transformation include the rise of China, the digital revolution, and the triumph of right-wing populism. Following its reform and opening up, China emerged as the first peer competitor to the US in over a century, while digital technologies turbocharged globalization and triggered deep social and political upheavals.
Today, the US faces an internal crisis with the erosion of its democratic institutions and the rule of law, while the external world sees a retreat of democracy and rising geopolitical tensions, echoing the pre-1914 era. Although nuclear weapons and the pursuit of prosperity reduce the risk of great power conflict, collective challenges such as climate change and AI management continue to test humanity's future.