No nation had greater incentive to secure their borders than Israel. They tried other means and failed. They finally built a wall and succeeded. It isn’t 100% secure, but terrorist incursions declined drastically.
A wall won’t completely eliminate drug smuggling across the border, but will confine it to cumbersome and expensive means, like tunneling. But they won’t be able to send tens of thousands of people across our borders illegally every month through tunnels.