Donald Trump’s executive order to build a wall between Mexico and the United States overlooks how the fences, walls, and border-control measures that already exist between the two countries have come to act as a barrier—or a “cage of gold”—that discourages migrants from leaving the United States, rather than preventing their entrance in the first place.
https://www.theatlantic.com/politics/archive/2017/02/trump-wall-migrants-immigration/516000/
