what could he mean by thispic.twitter.com/XvsYK5xmb6
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if you need someone in place to prevent a breach, a tower is a superior vantage to the ground if you don't, no reason not to automate vision or at least run remotely rather than pay lots of people to wander around at the base of a wall
I'm p sure the philosophy is surveillance + wall as an obstacle slowing any movement to aid border patrol in responding--they can't just do this in a bunch of towers spread thin
in that case, cameras
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