Something to consider here is that the Panama Canal has actually become LESS important for containerized cargo over time. There are a couple of factors at work here:
1. In many industries, high-volume manufacturing in Asia has slowly migrated south and west from China, Japan, Taiwan and Korea to places like Malaysia, Indonesia and Thailand. Singapore is the "centroid" of Asia for supply chains to North America. It's almost exactly equidistant in either direction to the East Coast of the U.S. from there ... so shipping to the U.S. from posts west of Singapore is more efficient via a westbound water route through the Suez Canal than eastbound through the Panama Canal.
2. California is a major consumer market itself, but most of the cargo coming through the LA/Long Beach port complex is destined for other parts of North America. In many respects, those ports may be more of a nuisance than they are worth -- especially when you consider the local impacts of traffic congestion, noise and diesel emissions.
My company trades products like LVP flooring that almost exclusively comes from China in a container.
It is all brought into the port of Long Beach. So, it may be cost prohibitive to truck that container all the way to Maine.
However, it will still be price competitive in OR or Idaho.
We bring a lot of lumber and OSB from Europe into the USA east coast. We have learned that some ports are much better to work with than others. Baltimore is great. Other places like Wilmington, DE suck because you can only pick up with an appointment.
Cape Canaveral is great. Easy to get trucks going north. Savannah sucks. You pay $1.50 more per mile out of the ports in the Carolinas than you do out of Florida. This affects where you can sell the lumber.
So, logistically it is always easier to get your product picked up in FL because about 5 trucks go into Fl for every one that comes out.
These are the things that affect which port you choose to send that product into. However, many times you do not have a choice. The manufacturer decides what port their products goes to because certain vessel lines only go to certain ports.
We have some lumber that comes out of Europe that has to go to either Baltimore or Houston. That is your choice. So, it may not make that product competitive into MN. It certainly will not work into the Pacific Northwest.