Put a moat filled with alligators in front of the wall.
I remember a joke email going around after Katrina that we should build a canal between the Gulf and the Pacific ocean.
We could use all of the dirt from digging it to fill in NOLA and bring it up above sea level.
Some one brought up the point it would displace a lot of Alligators which of course could be relocated to the canal!!
Not really a half bad idea, the canal would come in handy as well as serve as a secure border (moat filled with alligators)
Put a moat filled with alligators in front of the wall.
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If the wall was built on the actual Texas/Mexico border line you’d have water as the
middle of the Rio Grande river is the border in most locations.
Piranhas...lots of hungry piranhas.