The U.S. Financial Secretary has harshly criticised China's industrial overcapacity. This is odd. Overcapacity is the very foundation of international trade. If each country can produce just enough for itself, what is the point of external trade?

There is overcapacity of many things in the U.S. , from surplus bankers to cosmetics, cars, toothpastes and iPhones. A good reason for trade is you have "comparative advantages" in making certain products. When the U.S. loses a battle, it always resorts to bullying tactics - as we have just seen.