Funnelling “problems” to known points is better than pushing those problems to any of a bazillion other points.
But i guess ticking “we did something” checkboxes keeps the paycheck deposits flowing.
Apprehensions on the northern border usually want to be found, as asylum claims. Anyone who wants to cross illegally at the northern border could easily do so since forever. So in this case the bazillion other points land in Canada, since those that wanted to illegal into the US from the North always could. That's a "win" for the US from the perspective of the administration.
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