Expansion can take place in Mexico with little impact on anybody.
The Texas Gulf Coast and LA I’d guess are looking forward to any expansion of the Panama Canal as that will let the larger container vessels into the Gulf. Walmart has already built a 4 million sq. ft. distribution facility in Houston that imports up to 28% of their Asian goods via the Panama Canal on smaller ships with an added 3000 mile shipping distance. But it has cut days off their ontime destination delivery to their retail outlets. The strike at the West Coast ports during the Christmas season of I think 2002 causesd Walmart to rethink their importation system and Houston was the benefactor.
Think Prince Rupert and you’ll find a new facility in British Columbia being built to bring in Asian goods. This is the deepest port on the Continent and the northern rail head of the Canadian rail system. Memphis here we come.
They have this Fall thing up there though ~ 14 meter waves ~ comes just about every year ~ just in time for Christmas!