By following a playbook that will be quite familiar to U.S. shoppers, Coupang has come to dominate e-commerce in its home market.When U.S. investors hear the word "e-commerce," it's natural for them to think of Amazon, the company that redefined how people think about shopping online. But they may easily overlook one company in Asia that's following the Amazon playbook and putting up impressive results.Coupang (CPNG 3.41%) now dominates the South Korean e-commerce space, and it's continuing to add products ...