Instead of building a wall along the border, why not something fun?
Perhaps a ball pit, like they have at Chuck E Cheese and McDonalds.
Then, families trying to cross the border will have to fish their kids back out of it.
“COME ON, MOM!” they will shout. “FIVE MORE MINUTES! PLEASE?”
And then it will get dark, and they’ll have to get home.
If they leave the kids behind, they will sink to the bottom of the ball pit.
And fall through chutes to The Organ Havresting Factory.
Oops. I meant to say The Ice Cream and Unicorns Room.