The dependency goes both ways. We could cut off potash and they'd starve. We could cut off the oil and electricity. We could cut off steel and aluminum. The response would not be pleasant, but neither can they afford to risk our response. As dire as the trade-war seems, it doesn't affect even 5% of cross-border trade. No matter what Trump claims about "not needing" anything Canada has, we are dependent on each other.

Broadening our trade is similar to building a new oil pipeline. Nobody is sure a new pipeline will ever pay for itself, but one we started a decade ago would be making us a fortune right now. Trade diversification won't help us much in the current trade war, but it could help us out considerably in the next one.

Trump is a symptom, not the root cause. He may die of old age soon and MAGA may go dormant for a few years if the midterms and/or 2028 election beat them down sufficiently, but they'll be back eventually with some other clown at the helm. Americans voted Trump in twice. They'll vote clown again, and having options will help Canada when that happens. American checks and balances no longer work. If we'd known this was going to happen ten years ago we'd be in a better position today. Now we know it's likely to happen again in another ten or twenty years, so we'd be fools not to prepare.