Pet phrases are a substitute for the effort of understanding complex issues or real people. Cheap nannies. Radical socialism. Liberal elite. Open borders. Cities in flames. These phrases should induce narcolepsy, not interest.
Since border policy has always been racist the phrase "Open Borders" is a racist dog-whistle. Anyone who uses that term as an argument against a political ideology is a racist.
Bunkum!
When mrs bambu entered Canada by air the border was not open, she couldn't just walk thu the terminal and keep going....she had to apply for a visa and get a passport before she left home...make sure she had all the documents, and her medications and prescriptions ready for inspection by Customs.
Same deal when she entered the US from Canada...fingerprints taken, photo taken, passport and US visa produced, medications declared and ready to produce.
She can be seen as being White or non-White depending on the lighting, sunshine or cloud, and whatever if any glasses you're wearing.
In the EU though, you can move from one country to another with none of that. Look how that "open borders" nonsense there has worked out...very badly, it's a failed policy.
And she was just going for a holiday.