Two key Southern California ports demonstrate how voluminous the trade between China and the US is and the effect that tariffs could have on that business. O'Connell warned that a long-lasting decline in trade volume between China and the US would have a major impact on employment among blue-collar workers in Southern California. Out of the $145 billion, $134 billion worth was goods imported from China, and $11 billion was goods exported from the US to China. The port generates 300,000 jobs across Southern California, and there are 5,000 dockworkers and 10,000 truck drivers working there, Peterson said. Cheung said a reduction in trade activity could hurt the logistics sector, especially jobs tied to the moving of goods in the ports of Los Angeles and Long Beach and at Los Angeles International Airport.