The public will remember the Trump administration’s border policies for its visual horrors: a mother pulling her children away from tear gas launched over the border by US border authorities, Border Patrol agents dumping water left for migrants by aid groups, children sitting alone in chain-link cells after being taken from their parents. The cruel and complicated mess of Trump’s policy shifts could fill a small book, but it never made the same impression on the average observer. Images and symbols drove public anger. And over the last four years, there has been no clearer representation of Trump’s anti-immigrant fervor than the border wall.

After four years of outrage, the Biden administration faces a dilemma. Its voters expect a change, but many of his advisers fear a border surge and are torn between competing visions of immigration policy: Is it primarily a humanitarian or a national security issue? As part of a series of day-one executive actions, the president halted construction of the wall and stopped new enrollments in the Migrant Protection Protocols program, which forced asylum seekers to wait in often-dangerous circumstances in Mexico for their US immigration hearings. He has yet to say what exactly he’ll do about the thousands of troops stationed along the border, but we can generally expect him to pursue a softer, less militarized public image of border enforcement.

An enticing alternative is the “smart” wall, where advanced surveillance tech replaces steel bollards and armed patrol routes. While the full text of the immigration legislative proposal Biden sent to Congress has not been made public, a fact sheet distributed to reporters contains a section titled “Supplement existing border resources with technology and Infrastructure,” which calls for additional funding to, among other things, “enhance the ability to process asylum seekers” and “manage and secure the southern border between ports of entry that focuses on flexible solutions and technologies that expand the ability to detect illicit activity.”

Many Democrats have embraced aerial drones, infrared cameras, motion sensors, radar, facial recognition, and artificial intelligence as more humane ways to reach the shared, if somewhat amorphous, goal of border security. “It has been easy for politicians to point to border security technology as a fallback option if they just don’t like the idea of physical barriers,” said Jessica Bolter, associate policy analyst at the Migration Policy Institute. These implements have the veneer of scientific impartiality and rarely produce contentious imagery, which makes them both palatable to a broadly apathetic public and insidiously dangerous.

Unlike a border wall, an advanced virtual “border” doesn’t just exist along the demarcation dividing countries. It extends hundreds of miles inland along the “Constitution-free zone” of enhanced Border Patrol authority. It’s in private property and along domestic roadways. It’s at airports, where the government is ready to roll out a facial recognition system with no age limit that includes travelers on domestic flights that never cross a border.

A frontline Customs and Border Protection officer, who asked not to be identified as they were not authorized to speak publicly, told The Nation that they had concerns about the growth of this technology, especially with the agency “expanding its capabilities and training its armed personnel to act as a federal police.” These capabilities were showcased this summer when CBP agents joined other often-unidentified federal forces in cities with Black Lives Matter protests. The deployments included the use of ground and aerial surveillance tech, including drones, as first reported by The Nation.

This sort of mission creep illustrates the folly in complacency over the use of advanced surveillance tech on the grounds that it is for “border enforcement.” It is always easier to add to the list of acceptable data uses than it is to limit them, largely owing to our security paranoia where any risk is unacceptable. It’s the same mechanism that stops politicians from reducing bloated police budgets: Do so, and you run the risk of having one grisly crime be your political undoing. “The oversight committees are not providing oversight,” the CBP officer said, referring to the congressional committees that have purview over homeland security and technology.

To an extent, these technologies’ ability to fade into the background can leave them relatively invisible to domestic audiences—until suddenly they’re not. Take the no-fly list, which is more like an unreviewable no-fly algorithm. Every time someone tries to check in for a flight, their information is sent to the Department of Homeland Security (DHS), which makes real-time decisions about whether they’re allowed to board the plane or not. If rejected, you are given no reasoning, shown no evidence, given no process by which this decision was reached, and have few avenues for redress. Even the specific criteria used for such determinations is secret. It’s a tool that many Americans might agree with on principle, but it has expanded into a tool of wanton state power without any public discussion. “People are shocked to the point of near disbelief when you tell them this is happening. It doesn’t occur to them that there’s an invisible checkpoint at the airport,” said Edward Hasbrouck, a consultant with the Identity Project and writer at the affiliated Papers Please blog.

Hasbrouck believes the principles applied at airports will be extended to the physical border. He said DHS officials “complain constantly and explicitly about the fact that, unlike at the airport, where we know who’s getting on the plane before they get on the plane, at the land border anybody can just show up. They regard this as a horrible defect that they’re working assiduously to rectify.” The language in the immigration bill fact sheet points in the direction of technological processing of migrants in a way that will limit their ability to just show up.

This is particularly concerning given the changing demographics of border arrivals. In the early 2000s, the typical unlawful crosser was a single male from Mexico seeking work in the United States. Today, the bulk of those arriving without documentation are asylum seekers, especially children and families after humanitarian protection. The Trump administration has been laser-focused on tamping down access to asylum, but the more sympathetic Obama administration never figured out how to effectively deal with this shifting population either. The Obama White House, not Trump, built the now-notorious family residential centers, the “cages” that caused such controversy.

Trump adviser Stephen Miller’s strategy has been to push the border south under the often-correct assumption that for the American public out of sight means out of mind. The squalid refugee camps created by the Migrant Protection Protocols program are just across the border, and have gotten a fraction of the attention of other border abuses. For an administration hoping to sidestep domestic controversy over the treatment of desperate migrants while still set on controlling their flow and entry, the use of technology to develop what Hasbrouck called a “kind of pre-approval that externalizes and moves the borders further and further away” might seem like the best option.

Everything about our society has been affected by the Covid-19 pandemic, and immigration enforcement is no exception. Seth Stodder, who served stints in Homeland Security in both the Bush and Obama administrations, most recently as assistant secretary for border, immigration, and trade policy, said one of the primary immigration technology questions in the near term is: “How do you evaluate technology needs to have reliable verification that people have been vaccinated, or they’ve actually taken screening tests and things like that?”

In this interim period where the vaccines are widely available only in some areas, Stodder said there has to be a tech-driven solution to balance health concerns with a desire to remain open to travel and humanitarian entry. “Do you start totally liberalizing travel between the rich world that has been vaccinated and then sort of shut out the other world? I hope not,” he said. Wednesday’s slate of executive actions neither rolled back Covid-19-related travel bans nor repealed the controversial Centers for Disease Control and Prevention order that has served as the basis for the expulsions without due process of hundreds of thousands of would-be asylum seekers.

Some of the solutions floated so far are concerning from a civil liberties perspective. In an article for the trade publication Border Security Report, two PricewaterhouseCoopers consultants write that governments can integrate different data streams, pointing to Taiwan’s effort to combine immigration and health databases so authorities can immediately check patients’ travel data. They also advocate leveraging the “sensors and connectivity facilities” of the globe’s 3.5 billion active smartphones for active monitoring, while acknowledging the potential for abuse. New technologies like AI-equipped thermal cameras, which can supposedly detect fevers, could act as a dragnet for anyone even suspected of having the coronavirus. Once the vaccine rollout is further along, international travel to certain countries could start requiring some sort of certificate of vaccination, like another passport.

Whatever its direction, there will likely be an expansion of immigration and border technology, and it will involve a slew of private actors. In 2011, Obama infamously canceled a years-long “high-tech border fence” project that had accomplished little except provide $1 billion in taxpayer funds to Boeing. Yet technological capabilities have improved dramatically since then, and the vision of a pervasive and interconnected travel surveillance apparatus is now more realizable. Entire companies have formed to cater to these contracts, including Anduril, headed by crypto-fascist troll Palmer Luckey, who has close ties to mass surveillance firm Palantir (not coincidentally, both are companies named after objects from Lord of the Rings, by people who probably cheered the villains’ quest for absolute power).

Anduril has already received over $60 million in contracts from the DHS, including for high-tech pilot programs utilizing laser-equipped cameras, radar, and pattern-recognition software to detect border crossings. Other defense and security contractors are creating the infrastructure to ingest and manage millions of immigration applicants’ and US sponsors’ sensitive biometric data, including voice prints and DNA, in what Hasbrouck termed the “unholy alliance” of public and private surveillance interests and efforts.

There are already few limitations on the ability of immigration agents to access and use the information held in federal databases or to conduct additional surveillance when and where they see fit. Even then, the restrictions that do exist are easily sidestepped by going commercial. The DHS, for instance, simply buys phone geolocation data on the open market to avoid the hassle of obtaining a warrant.

Much of the danger with these technologies emerges when they’re used in tandem with each other. Each individual tool might make sense as a standalone technology, but the relationship models and pattern recognition enabled by the DHS’s massive databases and the interfaces provided by a company like Palantir are incredibly powerful together. License-plate readers can pick up the movements of a car; phone location and long-range RFID data can tell you who is in the car; social media and contact webs can tell you who those people know and interact with; and so on.

So far there are signs Biden intends to cautiously transition to some sort of virtual border. In addition to the language in the immigration bill fact sheet, his campaign immigration plan chastised Trump for failing to “invest in smarter border technology coupled with privacy protections” and featured a pledge to invest in tools like “cameras, sensors, large-scale x-ray machines, and fixed towers.” The fact sheet also notes that “to protect privacy, the DHS Inspector General is authorized to conduct oversight to ensure that employed technology effectively serves legitimate agency purposes.” While this inclusion is welcome, without clear enforcement mechanisms it will be an empty promise.

For over a decade, the DHS has ostensibly ascribed to the privacy-minded Fair Information Practice Principles, yet it continuously violates them with its unfettered data collection and usage. CBP’s own inspector general has criticized the department for not taking privacy seriously. The president’s picks for key cabinet-level positions have a distinct getting-the-gang-back-together feel. The inclusion of former White House Domestic Policy Council head Cecilia Muñoz enraged immigration activists who hold her responsible for the enforcement machinery that earned Obama the moniker of “deporter in chief.”

Any pushback to the smart-wall concept would likely be coming mainly from activists and progressives in Congress, and there has been considerable friction already between the grass roots and the incoming administration. Biden-world figures told reporters that they find the activists abrasive, and moderate Democrats blame progressive sloganeering for a lack of electoral victories.

Still, Bolter believes that the end of the never-ending emergency that was Trump-era immigration policy may leave both activists and oversight actors with the time and resources needed to keep an eye on border technology. “If this becomes the focal point of the Biden administration’s border security plan, I think there’s going to be a lot more scrutiny,” she said. “There’ll have to be a shift in the oversight priorities, when Congress doesn’t have to be spending all their time talking about separated families or the border wall.”