Business groups tell Obama that the use of a mediator is imperative in longshore union talks.
Employers "hopeful that this will allow us to move toward conclusion of an agreement in the near term."
Ports, airports and railways ready to implement winter contingency plans.
Port director's tenure has seen projects to deepen harbor, raise Bayonne Bridge, expand marine terminals and intermodal rail.
Hueneme CEO says port could offer relief valve for congestion.
Consensus shows better growth than other parts of world.