China’s top 10 exporters include American companies with Chinese operations, such as Motorola and Seagate Technology, a maker of disk drives for computers. Intel now produces some 50 million chips a year in China, the majority of which end up in computers and other goods that are exported to other parts of Asia, or back to the United States. Yet Intel’s plant in Shanghai doesn’t really make chips; it tests and assembles chips from silicon wafers made in Intel plants abroad, mostly in the United States. China adds less than 5 percent of the value. The U.S. operations of Intel generate the bulk of the value and profits.