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The American President Donald Trump has announced plans to prioritize pursuing a border wall with Mexico. But will it be effective?

According to, walls can actually work. The article mentions various precedents of walls and systems designed to maintain security and keep illegal immigrants and terrorists out while allowing legal immigrants and visitors in. Among these are Israel’s West Bank security fence; Morocco’s 1,700-mile system of sand berms, fences, mine fields, and ditches along the Algerian border; the Indian border fence and wall system to keep Pakistanis out; Turkey’s border with Syria, along which fences and mine fields were deployed; Saudi Arabia’s newly built wall along its disputed border with Yemen to keep Yemeni-based terrorists out of the Saudi Kingdom, and several other walls in conflict regions.

During and before the Obama administration, US policymakers concluded that a US-Mexico border wall would not be feasible. The border is 1,954 miles long. While more than 700 miles of border fence exists, the fenced border remains porous with drug cartels and people smugglers constructing tunnels under the border, cutting holes through the fence, or simply climbing over it.

The question is actually which technologies can be employed effectively. According to, the US Border Patrol has more than doubled its forces following September 11, 2001. The Customs and Border Protection (CBP) screens 100% of southbound rail shipments for illegal weapons, drugs and cash, and it has expanded its Unmanned Aircraft System (UAS) efforts at the Southwest border, including the approximate 650 miles of existing fencing. The CBP uses canine teams, non-intrusive inspection systems, mobile surveillance, remote video surveillance, thermal imaging, radiation portal monitors and license-plate readers in the protection of the Southwest border.

Scanning – the terrorist attacks spawned a company called Passport, founded in 2002 that delivered two commercial scanners: the SmartScan cargo scanner, for use at borders and seaports; and a wireless radiation-monitoring system, for use at public events. Passport’s technology provides precision scanning in minutes, without opening a container.

Sensors, Cameras and Communications – Tucson, Arizona’s 90,000 sqm of desert is guarded by nine tall towers complete with sensors, radar, and daytime and infrared cameras. Each one is in line-of-sight with at least one other tower, and all are linked via microwave communications that transmit imagery to a control room in real-time. Radar scans are constant.

A mobile video surveillance system (MVSS) adds a laser range finder mounted on trucks to complement the towers. There is also a system of underground sensors buried in the desert that trigger alarms when they detect movement. Support is also available from airplanes, helicopters and, increasingly, drones.

Approximately a third of the Southern border is already fenced and is effective at making crossing more difficult; the balance is guarded by Border Patrol. The fence, however, only protects the flat areas of the boundary, ending at steep terrain. The estimated cost to build a fence that spans the entire border is $22.4 billion.

So what will be the technology employed? So far, vetting and facial recognition technology are the two suggested solutions (after walls and fences). Extreme vetting, however, requires improved and smarter data. According to Donna Roy, executive director of the DHS’ Information Sharing and Services Office (ISO2O), she is working with the intelligence community on standards related to extreme vetting. She also indicated that facial recognition technology could be an important aspect of extreme vetting.