The shutdown would be due to the differences between employers and workers, for which they have been bargaining collectively since May last year.
The current port congestion is causing difficulties in operations, and according to some executives, such as James McKenna, president of the Pacific Maritime Association, this could lead to a collapse of operations in the ports on the west coast of America so they would be forced to paralyse operations; a scenario that has been denied by the dockworkers‘ unions.