Last October, a black bear was caught on camera trying to cross the U.S.-Mexico border in southeast Arizona. In the video, the bear can be seen poking his snout through a steel fence built to block vehicles; the gaps between the posts are also too narrow for ursine shoulders. Sky Island Alliance, the binational conservation group that released the footage, has recorded members of at least a dozen species interacting...
In 1990, there were fifteen international border walls, according to the political geographer Reece Jones. Today, that figure has more than quintupled — and it doesn’t account for the vast surveillance apparatuses that track and criminalize migration even in the absence of brick-and-mortar (and chain-link, and steel) barriers. By 2025, the global border-security market is expected to generate more than $65 billion in revenue. These structures and systems haven’t stopped...