"The Bureau of Land Management (BLM) Encourages Visitors to Use Public Lands North of Interstate 8."
Just how far north is Interstate 8?
Click on that to see a much larger version. Red arrows point north at the International Border. Green arrows point south at Interstate 8. Granted Interstate 8 runs about 20 miles north of the International border where it passes through Yuma near the Arizona-California border. But, the problems aren't in the Yuma Sector (approximately the western half of Arizona). The problems are in the Tucson Sector (approximately the eastern half of Arizona). As you can see, Interstate is as much as 80 miles from the border.
So, just how much of Arizona have we ceded to the armed invaders? Blue line is roughly an outline of the State of Arizona. Again, green arrows point south at Interstate 8 and red arrows point north at the International Border with Mexico. Looks like about 10%.