现代全球化对比较优势理论的挑战
现在的全球化不同于早先的全球化。我们知道，经济全球化的理论基础之一是比较优势理论。比较优势理论是两百年前由英国经济学家李嘉图提出的。按照比较优势理论，如果每个国家都集中生产并出口自己具有比较优势的产品，进口其具有比较劣势的产品，那么到头来，交易双方都可以增进自己的利益。然而，李嘉图的比较优势理论是建立在一系列理论前提之上的，其中很重要的一条是，生产要素在一国之内可以自由流动，在两国间则不能流动。在李嘉图的时代，国与国的自由贸易只限于产品。在当时，资本和私人企业是不会移动的，是留在本国的。今天的经济全球化，却是在产品自由流动之外，还加上了资本和私人企业的自由流动。人员的流动也增加了，不过人员的流动总有各种障碍，因而总是缓慢的、有限的；而资本的流动则易如反掌，十分快捷。既然比较优势理论赖以成立的理论前提发生了重大改变，因此，原先从比较优势理论推出的结论也就不一定还成立了。
不错，中美之间的经济交往与贸易给两国的经济都带来了可观的收益，但是在一国之内，不同群体的收益情况却可以很不相同。在美国，跨国资本是最大的受益者，而失去工作的劳工则是相对的乃至绝对的受害者；在中国，最大受益者是政府。另外，两国的受益情况也不等同，总的来说，中国受益要比美国大。
The current globalization is different from the earlier form of globalization. As we know, one of the theoretical foundations of economic globalization is the theory of comparative advantage. The theory of comparative advantage was proposed by the British economist David Ricardo two hundred years ago. According to this theory, if each country specializes in producing and exporting goods in which it has a comparative advantage while importing goods in which it has a comparative disadvantage, both trading parties will ultimately benefit. However, Ricardo's theory of comparative advantage is based on a series of theoretical assumptions, one of the most important being that factors of production can move freely within a country but cannot move between countries. In Ricardo's time, free trade between nations was limited to products. At that time, capital and private enterprises did not move across borders; they remained within their home countries.
Today's economic globalization, however, goes beyond the free movement of products to include the free movement of capital and private enterprises. Although labor mobility has also increased, it still faces various obstacles and is therefore slow and limited, whereas capital flows with ease and at a rapid pace. Since the fundamental assumptions supporting the theory of comparative advantage have undergone significant changes, the conclusions originally derived from this theory may no longer hold.
Indeed, economic interactions and trade between China and the United States have brought considerable benefits to both economies. However, within each country, different groups experience different outcomes. In the United States, multinational capital is the biggest beneficiary, while workers who have lost their jobs are relative or even absolute losers. In China, the biggest beneficiary is the government. Additionally, the overall benefits are not equal between the two countries; generally speaking, China has gained more than the United States.