I agree that where there is demand, profit motive will provide a product. And I suspect demand in the good ole US of A isn’t going away anytime soon, no matter what Nancy Reagan said. The other thing not going away is the political pressure to rid the US of drugs.
The way I look at it is kind of like NATO defense spending. The border is a line on a map. It can be secured on either or both sides of the line. But if it’s only be done on one side, the other side is getting a free ride. So, I think it’s fair for Canada and Mexico to contribute to border security similar to NATO countries contributing to defense. If Canada doesn’t spend the two percent (and Canada is one of the worst NATO countries for spending) it means Canada is getting a free ride on national defense. Universal healthcare and the public pension gets funded instead. If Russia decides to invade Cape Columbia (I looked up Canada’s northern most point), guess who’s launching the cruise missiles at the Ruskies? I guess there has been a surge of crossings at the northern border. I kinda doubt the Mounties are doing much heavy lifting on border security.
Now, Mexico is a lot messier, for a lot of reasons. One of the big things is Mexico needs to secure (and keep secure) its own southern border. That stems the flow of migrants from Central and South America. Trump wants remain in Mexico back too. He seemed to get what he wanted on both those points in his first term.
And of course, the USMCA hitting its “joint review” in 2026 should not be overlooked. The parties are supposed to discuss revisisions, and each must submit a notice to extend the agreement, or it will ends in 2036. Trump will obviously leverage that to the hilt.