I read recently about the wall that Mexico has erected on it's southern borders to keep people out. Hmmm

The problem of people and drugs crossing the US Southern Border warrants tighter border security. We've known this problem existed at least since the early 20th Century (look up "Black Jack" Pershing's career). The US has patrolled the border with the personnel and technology available at the time since at least the 1940s. Remember the Germans attempted to get Mexico to enter WWII on their side. By the time I went to pilot training at Laughlin AFB, TX, in 1969-70 the Border Patrol was using Piper Cubs (a.k.a. O-1s) to patrol along the Rio Grande. During the Reagan Administration I was part of a study that looked at sealing the Southern Border in response to the drug problem. We determined the approximate quantity of military personnel and materiel needed to do the job on land, sea, and air. It's a lot.

The latest discussion about a "big, beautiful wall" really has two branches. The physical wall is a tool in border security. It might be concrete or steel fencing. It's purpose is to clearly define the border and cut down on the easy transit of people across the border. If you force those trafficking in people and drugs to dig a tunnel or at least bring a ladder, then you have inhibited their business and increased their cost--good things. Like the wall in Game of Thrones, it isn't very useful if it isn't properly guarded. The Border Patrol will need the resources to guard the wall using the latest technology including drones, ground penetrating radar, all types of sensors, and perhaps most of all the people to operate the technology and respond to any incursion. They also need rules of engagement that allow them to enforce existing laws with the highest level of intensity consistent with those laws, including the use of deadly force in defense of their lives or the lives of others in immediate danger.

The wall also is a symbol of national will. A determination to maintain our nationhood in the face of political and social Globalists who wish to rob us of our national sovereignty. A borderless nation becomes no nation at all. In the case of the USA, open borders negatively impact labor and wages, encourage the flow of illegal drugs into the country (yes, we create a market for them), and open us to the specter of terrorists invading our nation and killing our Citizens. The wall and increased border enforcement say, "enough!" We intend to protect and defend our nation.

Walls are still very effective at separating items. Most of us live in fenced homes none of us expect a fence to keep individuals out of our property but we all know very well that if an individual crosses the fence without permission it is a clear identifier of a hostile act, any rational person would have used the front door. In engineering class they teach any obstacle not under surveillance can have at best a disrupt effect. Drones and border patrol reinforce the wall, but are far more effective at there jobs when there is a wall because it removes the "I didn't know I just got lost" excuse. The wall also presents the psychological effect that says stay out unless you are invited in.
What we need to do is tighten the wall and increase the front door. We need programs to allow all illegals in this country to get SSN's and start paying taxes the legal way, free from reprisals. Then we need a tight stance that if you are arrested for any small infraction and cannot justify your expenses or livelihood with reportable income you are deported along with your financial dependents. Give some time to allow for registration then commence deportations en mass for only those illegals who refuse to register with the Government and start working legally.