Today, the US remains the world’s essential power, but it is no longer the exclusive power. It cannot solve problems that directly affect it by acting on its own, though its leadership remains indispensable.
二十年前，地缘政治环境限制了美国外交政策真空的回力。如今，美国仍是世界最重要强国，但已不再是唯一的强国。美国不再能够单枪匹马解决直接影响自身的问题，尽管美国的领导仍是不可或缺的。