Walls can be very effective in certain areas just ask the people who work there
Trump's wall! HAHAHAHA
Test of steel prototype for border wall showed it could be sawed through
The Trump administration directed the construction of eight steel and concrete prototype walls that were built in Otay Mesa, California, just across the border from Tijuana, Mexico. Trump inspected the prototypes in March 2018. He has now settled on a steel slat, or steel bollard, design for the proposed border barrier additions. https://www.democraticunderground.com/10142240344