Throughout the campaign, Donald Trump promised to build a wall along the United States and Mexican border. This is not a new proposal; a wall has been discussed, and partially built over about 40 percent of the border, in the past few decades. Connecting the sections and making the barrier stretch from the Gulf of Mexico to the Pacific Ocean, however, is fraught with complications and not favored by most Americans, according to polls.

The border history and current wall

The U.S.-Mexico border is approximately 1,933 miles long. It cuts through bustling towns, desolate desert, rivers and other rough terrain. At present, there are 48 official border crossings used for 350 million legal crossings annually.

Most of today’s border was established in the 1848 Treaty of Guadalupe Hidalgo at the end of the Mexican-American war. The demarcation between the four U.S. and six Mexican states along the border were established then, except the parts defined by the Rio Grande. That ongoing dispute was settled with the Boundary Treaty of 1970.

The first fencing along the border was built in 1990 near San Diego. Since then, various sections have been added as a barrier along 700 miles of border. Much of this was part of the Secure Fence Act of 2006, which was signed by President George W. Bush and largely implemented under President Barack Obama.

One of the most fortified areas separates areas of San Diego, California, from Tijuana in Mexico. That area has 10-15 foot high double and even triple fencing. Otherwise, the type of fencing varies by terrain, including sections constructed with barbed wire, tall steel barriers, concrete barriers for vehicles, chain link, post and rail, and X-shaped beams to thwart livestock.

The 2006 legislation also called for use of twenty-first century technology, so a “digital wall” now exists. It incorporates cameras, underground sensors, mobile surveillance units, aircraft and drones.

Advantages and disadvantages of finishing and fortifying the wall

The primary advantage to building a border wall is restricting entry. Illegal border crossings and drug trafficking have long been a problem, though illegal entries have reportedly declined and more Mexican nationals are leaving the U.S. lately.

Exact specifications have not emerged, but Trump has mentioned a “big” wall. Estimates are that a 15-foot concrete wall stretching along the whole border would be a massive infrastructure effort that would create many jobs and boost the construction sector. The short-term economic advantages would be on both sides, since Mexico is home to some of the largest cement producers.

There is also a theory that savings on support for illegal immigrants could pay for the wall. They each create an estimated financial burden of approximately $74,722 over their lifetimes, according to National Academies of Sciences, Engineering, and Medicine (NAS) data. This excludes costs for any U.S.-born children.

There are considerable disadvantages and dissent against building a border wall:

  • While Trump rally-goers convey their enthusiasm for a wall, only 37 percent of Americans favor building it.
  • When Bush’s administration was planning much of the current wall, they found that much of the difficult terrain would make the costs exorbitant. Current cost estimates for the remaining 1,000-plus miles of wall range from $27 billion to $40 billion, which on campaign Trump promised would be borne by Mexico.
  • To pay for the wall, the White House has floated the idea of taxing imports from Mexico. They would ultimately mean U.S. retailers and consumers would absorb the cost. U.S. companies with manufacturing plants south of the border, such as automakers, would be hurt. Additionally, there would undoubtedly be a backlash against U.S. companies operating in Mexico (e.g., Starbucks and Walmart).
  • Even if funding is garnered, land ownership is a huge issue. The government had to engage in negotiations and condemnation proceedings to build what is there. Areas without no fencing go through private property, Indian reservations and the Rio Grande region. The 1970 treaty on the latter specifies that structures cannot disrupt the flow.
  • No wall will keep everyone out. Smugglers will still dig tunnels and drones can now deliver contraband. At his confirmation, Department of Homeland Security Secretary General John Kelly acknowledge a physical barrier would not do the job.

Obama’s stance on a wall and illegal immigrants versus Trump’s 

During his term, President Obama actually was tough on illegal immigrants and border security, largely in a post-9/11 environment. His administration oversaw construction of parts of the wall that does exist and implemented some of the technological surveillance tools. Additionally, Obama oversaw more deportations in his eight years than Bush or President Bill Clinton did in theirs.

Trump’s administration wants the wall to keep people out and has indicated plans to deport anyone here illegally. Clearly, the new president envisions the wall much like China did – to stop invaders from entering the country. This is very different than policies set by predecessors that allowed for freer trade and relations between the U.S.-Mexican border.