Some former smugglers say a border wall wouldn't have stopped them from bringing people and drugs into the U.S. But border patrol agents are confident it will.
Chris Cabrera of the National Border Patrol Council says a wall would work, but it needs help.
"We need the camera sensors and everything we've got going on there and you need the personnel -- you need personnel to do anything -- to get in there and physically make that arrest and have that presence."
Cabrera says strong surveillance would keep people from digging tunnels.
"Once you have the surveillance, whether it's video or ground sensors that alert you to someone in the area, you can have somebody go check it out."
Cabrera says they'll never have time to dig an El Chapo-style tunnel system.
"And as good as some people are at digging under walls, for instance in the San Diego area, we have guys whose specialty is finding tunnels and closing them down."
Cabrera says we can't just build a wall by itself, but combined with high tech surveillance, it'll get the job done.
Smugglers claim they bring their stuff through ports of entry so a wall wouldn't have any effect on that.