" (The exhausted-looking people walking by the side of the road called to mind the current U.S. administration’s problems with Mexicans, but maybe I was reading too much into it)."

US administration problems with Mexicans? Oh, you mean the ones coming into the US illegally? The many criminals and gang members? Those, by any chance??

The US, like Canada, has a right and duty to defend and enforce its borders. Thankfully, under Trump illegal entry is down 70% and plummeting further. Trump is also getting tough on crime, criminals and gangs who have caused so much pain. Thank you President Trump for your bold leadership and courage. Much much better than Obama, who made things so much worse.