The Port of Vancouver just did 24.4 million metric tonnes and that’s just going to rise. Thanks for your (fake) concern but we’ll be fine.
Also, I explicitly said "energy". That includes electricity (you can't export that anywhere else really) and natural gas (almost all of which is used domestically or exported to the US).
Short term the US needs the energy we sell as they don’t have sources to replace it with. Long term the pieces are already moving into place for more O&G exports via the pacific and selling electricity to ourselves with stronger grid connections.
Our reliance on US trade will diminish slowly, then all at once.