I agree with you except on this point. The border is NOT clearly marked at all. Only in or close to urban areas is it clearly marked.
Some cases, you can't tell where the border lies.
My brother had a ranch in Corizo Springs, Texas. If he left the doors unlocked, the illegals would spend the night, take water, what food they could find.
If you locked the doors, the illegals would break in and trash the place. Spray paint Viva Mexico around.
Besides, most Americans have never been to the border, they know little about the valley here in Texas.
It is a complete cesspool. High crime, illegal drugs, prostitution, rampant diseases such as tuberculosis, malaria, parasitic infections...you get the point.
None of our senators or representatives would EVER go to the border as a civilian. They would never venture down to the valley where U.S. citizens are forced to live and endure this illegal invasion.
Trust me on this, I have been to the border and into Mexico many times....it would totally shock the average American to see the true face of these Mexican border towns.
The criminal offense is not so much the Mexican crossing the border, it is the treasonous acts of our elected officials letting it take place.
Can't speak to your brothers situation, but my son is a Border Patrol Agent in AZ and every inch of the border there is marked with a road and with at least a few strands of barb-wire. . . .all the way to CA. Except, of course, where ranchers are fighting the marking of the border (and some ranches extend over the border). Even on the reservations there are fences and a road.
The road is where the Border Patrol “drags” to smooth out the area so tracks may be more easily seen and the hunt begins.
In Texas, the border is clearly marked by a river. So I guess you are right, not a clearly man-made marking. . .but a pretty darned good natural border marker.
Anyone near the border knows where it is, no question. People just don't wander across the border and go; “Whoa, how did I get here?”
They cross deliberately. . .especially the Mexican Army.
The border is marked now until you get southeast of El Paso, Texas. There, the rough terrain, like around Presidio, is supposed to discourage them. The Texans put up a huge fight to prevent the construction of what fence there is there, especially in the Lower Rio Grande Valley.