Nursing a cup of strong coffee in a cafe near the port in Los Angeles, Esther Hudak is explaining how the world trade slump has hit her job prospects. “In 2006 I was working [at the port] four or five times a week,” she says. “I got out once last month.”

More than 40 per cent of US imports come through the San Pedro Bay ports at Los Angeles and nearby Long Beach, which have boomed for 30 years in line with the emergence of China as the world’s dominant manufacturing power.