Li Guilian has built Dayang Trands into a $300-million company that tailors clothing for some of the world's most famous brands and powerful people... Dayang is also the manufacturer behind those snappy blue blazers and white slacks designed by Ralph Lauren for this year's U.S. Olympic team... The dust-up comes at a time when American unemployment remains stubbornly high, fueling tension over China's massive trade imbalance with the U.S.