The invisible border — how 9/11 reshaped global security and identity 25 years later

Claudia Pizzocri contributes analysis, commentary and public insights for immigration and nationality law firm Eisenberg & Associates Inc.

As the sun set on Friday evening, 25 years after 11 September 2001, it was difficult not to reflect on how much of what followed that day had become part of ordinary life.

Many of us remember watching the tragedy unfold and understanding, even then, that they would become a permanent part of history. What was less apparent was how profoundly the response to 9/11 would change the way countries approached borders, migration and, ultimately, identity itself.

Twenty five years later, those changes barely register. We hand over biometric passports, submit fingerprints, allow our faces to be photographed at immigration counters and provide personal information before boarding an aircraft. Increasingly, people also hand over biometric details in the course of ordinary consumer transactions, sometimes simply to choose a haircut.

This did not all begin on 11 September 2001. The securitisation of migration was already the subject of considerable academic study before the attacks. In 2000, political scientist Jef Huysmans wrote of the “social construction of migration into a security question”, tracing how migration in Europe had progressively become associated with public order, crime, terrorism and national identity.

The 9/11 tragedy did not trigger the securitisation of migration, but it surely gave that ongoing process an urgency, legitimacy and technological momentum that would have been difficult to imagine before those attacks. Borders have since extended far beyond the territorial line separating one country from another.

Border control increasingly moved away from the border itself. It extended into visa application processes, to the airline before departure, to advance passenger information, watchlists and interconnected databases, and ultimately into the passport itself through biometric chips, fingerprints and facial recognition. Increasingly, travellers are identified, checked and assessed before ever reaching the physical border.

In 2006, Louise Amoore described this as the “biometric border”, raising early concerns about the use of technology to distinguish between forms of mobility regarded as legitimate and those regarded as a risk, with the identity of the traveller becoming part of the assessment itself. Those concerns are considerably less theoretical today, following two decades of rapid technological development and the introduction of AI into systems of identification, screening and risk assessment.

More recent research has described this “shifting border” as a “transportable legal wall” capable of shrinking, expanding and disappearing whereby immigration controls have progressively become detached from the geographical border itself: moved outside national territory in some instances, and further inside it in others.

The physical border has not disappeared but has been pre-emptively reinforced. Ports of entry remain places at which considerable public power is exercised.