I like how the people throw rocks, antagonize the border patrol agents, make them fear for their life, and the agents are expected to do nothing. We expect them to work in one of the most dangerous places in the US but, expect them to not use force be very diplomatic etc.
You know if that agent wasn't there that little shit kid would have ran across to the US. I'd have done the same thing, if a bunch of little shit bags were throwing rocks and shit at me and I gave them fair warning to stop, I'd have no issue pulling the trigger. One hits you and knocks you out, they could have killed or beaten you, taken your gun, kidnapped you.
Fuck it, that area is ruthless. There is no room for weakness.