Both Israel and East Germany seemed to have done the development work to get the best practices developed. Is it perfect? Heck no, but both a barrier array and patrols are required.Neither Israel nor German has miles of nothingness (reference the Brownsville to El Paso portion of the statement). Fences make sense near civilization, but ask Robert Kranze's widow how much the fence helped down by his place.
"Objection to a physical barrier is the pathognomonic sign (100% diagnostic) of an open borders illegal alien quisling."
I think that about covers it.