Borders are, & have always been, fundamentally open, because it's a plain physical (biological) reality that H. sapiens is a resourceful, migratory species. Ere

Borders are, & have always been, fundamentally open, because it's a plain physical (biological) reality that H. sapiens is a resourceful, migratory species. Erection of walls and legions of petty border-guarding popinjays is no more than a can-kicking exercise, a waste of time & resources analogous to those squandered pretending that climate change requires little response. You either face physical reality, or exert tremendous material effort on crass denial. Story-based entities (cultures, businesses, nations) are necessary but in the end, they are only temporary tactical fictions. They supervene on physical reality and when they attempt to deny it, will be swept away.