In the twentieth century, the United States took over that role, imposing its Pax Americana to provide security to most of Western Europe, Asia, the Middle East, and Latin America. The US also dominated the Bretton Woods institutions – the International Monetary Fund, the World Bank, and, later, the World Trade Organization – to determine the global trade and financial rules, with the dollar as the main reserve currency.
19世纪，英国牢牢掌握霸权，大英帝国供应全球公共品——自由贸易、资本自由流动、金本位和作为全球主要储备货币的英镑。20世纪，美国取而代之，建立美国统治下的和平（Pax Americana），向西欧、亚洲、中东和拉美的广大地域提供安全保障。美国也主宰了几个布雷顿森林机构——国际货币基金、世界银行以及后来的世界贸易组织，它为全球贸易和金融秩序定规，美元成为主要储备货币。