Doug Specht explores how a 520km barrier in the Atacama Desert could test the limits of migration control in South America
Silence has a particular quality in the Atacama. At nearly 4,000 metres above sea level, where the Andean altiplano rolls down toward the driest non-polar desert on Earth, the air is so thin and the landscape so vast that sound seems to dissolve before it travels far.
Andean flamingos stand motionless in crimson-tinged salt lagoons. Vicuñas, delicate, tawny camelids, ancestors of the domesticated alpaca, pick their way between boulders on slopes that have changed little since before human memory. The llareta, a fluorescent-green cushion plant that resembles a pile of moss but is in fact a dense flowering shrub, grows at roughly 1.5 centimetres a year; some individuals are three thousand years old.
Then, on 16 March 2026, five days after Chile’s new far-right president José Antonio Kast took office, the excavators arrived.
Within hours of his inauguration on 11 March, Kast had signed three immigration decrees, declared a national border emergency, and launched what his government calls the Escudo Fronterizo, the Border Shield. By the end of that first week, military machinery was digging trenches three metres deep into the desert floor near Arica, while troops were deployed in numbers not seen on these borders since the Pinochet era. The plan envisages 520 kilometres of fortification along Chile’s borders with Peru and Bolivia: trenches, walls up to five metres high, electrified fencing, motion sensors, thermal radar, surveillance drones, and biometric checkpoints. The deadline for initial infrastructure: 90 days.
What is happening in the Atacama is not simply a migration policy. It is an event that will reshape the ecology, the geopolitics, and landscape of one of the most remarkable corners of South America.
The man and the plan
José Antonio Kast, 60, is a former MP and the son of a German immigrant who has modelled much of his political identity on Donald Trump. His December 2025 election victory, with nearly 60 per cent of the run-off vote, represented Chile’s sharpest political turn since the military dictatorship ended in 1990. The US State Department welcomed Kast, and the Escudo Fronterizo model.
Polls on inauguration day showed 80 per cent of respondents also supported the border plan. Between 2017 and 2023, Chile’s foreign-born population roughly doubled to nearly 2 million. Some 336,000 undocumented migrants are estimated to be living in the country, and Kast’s campaign promise of “If you do not leave voluntarily, we will deport you with only what you have on your back”, resonated with a public increasingly encouraged to blame crime, and strain housing, and public services on migrant populations.
Kast’s rhetoric is now manifesting in a physical structure with consequences for real ecosystems and real communities, with consequences that will outlast any presidency.
The landscape in question
The country’s border zone with Bolivia and Peru is not the barren emptiness that casual cartography implies. The Atacama is the world’s driest non-polar desert, but the altiplano running along its eastern edge is a different kind of extreme environment: high, cold, windswept, and remarkably biodiverse.
At the Salar de Huasco, a high-altitude salt flat squarely in the border zone, three flamingo species breed alongside pumas and numerous other vertebrates. The Andean, James’s, and Chilean flamingos all depend on the specific chemistry of these saline lagoons, shaped by deep underground aquifers and seasonal Andean meltwater. All three are classified as Vulnerable or Near Threatened; their populations are already under pressure from mining and human disturbance. The border zone is also the habitat of the vicuña and the guanaco, the two wild camelids of the Andes, whose seasonal migration corridors cross the border routinely, shared with pumas, Andean foxes, and dozens of bird species.
Heavy machinery in Atacama terrain also compacts soil profiles and disrupts hydrological pathways in an ecosystem that recovers at geological, not human, timescales. The llareta that took three thousand years to grow will not return in any human lifetime.
There are also the Aymara, Chile’s far-north Indigenous communities who have managed these high-altitude landscapes for millennia. Their territories overlap directly with the construction zone, and their water sources, already threatened by lithium mining, pass through the land the Escudo Fronterizo will fortify. Under Kast, whose government has signalled a rollback of environmental protections, these communities expect less recourse to legal challenge, not more.
The funnel effect
On the desert floor, the trenches will not stop anyone. Since Venezuela’s economy began collapsing around 2015, an estimated 7.7 million Venezuelans have left their country, most travelling overland, on foot, across the Andes. For those heading to Chile, the final stage is the Atacama: nearly 4,000 metres above sea level, with daytime temperatures exceeding 40°C and nights dropping below minus 10°C. Many arrive in Chile with hypothermia, dehydration, and altitude sickness. Seven people died attempting this crossing in 2022; seventeen died in 2021. If the harsh Atacama is not a barrier to those desperate to migrate, the Escudo Fronterizo will surely not be either.
What the Escudo Fronterizo will do is produce the funnel effect. A barrier does not eliminate the forces driving migration, economic collapse, persecution, violence. It redirects them onto more remote, more dangerous routes entirely without humanitarian infrastructure. In 2023, when Chile temporarily restricted crossings, Amnesty International documented more than 300 people, including children and pregnant women, stranded without food, water, or medical care as their passage to Chile became blocked. Peru, alarmed by this spillover risk, declared a 60-day military state of emergency in its Tacna border region in November 2025, months before Kast even took office. The regional cascade had already begun.
The new map of Latin American politics
Kast is building this wall as part of a conscious continental alignment. Chile’s Escudo Fronterizo is the latest expression of a rightward turn reshaping South American politics. Javier Milei in Argentina, Daniel Noboa in Ecuador, Nayib Bukele in El Salvador, and Santiago Peña in Paraguay have constructed a loose axis of hard-right governments sharing a scepticism of multilateral institutions, a hostility to migration, and a gravitational pull towards Washington.
The vision of South America as a space of cooperative responses to shared challenges has effectively collapsed in the southern cone. The continent’s migration system, built on the Mercosur freedom-of-movement framework and UNHCR recommendations to protect Venezuelans, is being dismantled country by country, wall by wall. What is being built in its place is a security architecture that is bilateral, driven by national interests, and enforced by military means. Chile’s 520-kilometre fortification is its contribution. It will likely inspire others.
The ground beneath the trench
The excavators in the Atacama are digging through more than desert soil. They are digging through 140 years of geopolitical grievance, through fragile ecosystems that evolved over millions of years, through the desperate last miles of journeys begun 5,000 kilometres away in Venezuela’s collapsing cities, and through the aspirations of Aymara communities who have managed these highlands since long before any of the borders on this map existed.
The flamingos were wading in those red lagoons before the Spanish arrived, before the Wars of Independence, and before the War of the Pacific redrew the map of South America in Chile’s favour. The llareta has outlasted the rise and fall of civilisations.
What this landscape has never had to survive before is a five-metre wall running through 520 kilometres of it.The question the Escudo Fronterizo poses is one that geographers and policymakers have rarely confronted so directly: when we draw hard lines across the earth to manage the movement of people, what else do we divide? What else do we lose? And, in a desert where the ground itself remembers, in the slow growth rings of a three-thousand-year-old plant, can we be sure we know how to repair it?
