25 years of evolving rules: How 9/11 changed airport security of world forever? EXPLAINED

It has been 25 years since the 9/11 attack, but the aftermath of the incident still forces all nations to always focus on the security of their major infrastructure, that specially include airports, metro stations, railways and industrial areas. Out of these infrastructures, more focus and tight security come over the airports, as the September 11 attacks, in which four hijacked planes were used as weapons against the United States, left nearly 3,000 dead, sending shockwaves across the globe.

Earlier, families could accompany passengers all the way to departure gates as security checks were minimal. Even boarding a plane rarely meant long queues or extensive scrutiny, but things have suddenly changed after this attack.

Before 9/11 deadly incident, security at airports was relatively calm, as private contractors handled checks, with limited training and little uniformity in the United States. Earlier, passengers were also allowed to keep shoes on and liquids freely. In addition, cockpit doors were also not reinforced, and in-flight security protocols were very limited.

At that time, hijackings were common, as things were resolved through negotiations rather than violence, but it was shocking to witness the idea of weaponisation of the commercial plane.

How did 9/11 change flying forever?

The 9/11 attacks led to a major overhaul in how aviation security was approached. Within weeks, the US Congress set up the Transportation Security Administration (TSA), shifting airport security responsibilities from private contractors to a federal agency, aiming to standardise procedures and tighten controls.

Some of the earliest measures introduced included: reinforced cockpit doors to block unauthorised entry, passenger no-fly lists to flag potential security threats, random secondary screenings along with behavioural profiling, and a greater number of armed air marshals stationed on flights.

Other than these measures, screening technology has also advanced significantly over the past 25 years, with airports now using CT scanners similar to those found in hospitals. These machines generate detailed, three-dimensional images of luggage, enabling screeners to inspect its contents from various angles.

It has also implemented biometric systems, such as fingerprint and facial recognition, which are increasingly used to verify identities. In addition, Artificial intelligence is also being deployed to analyse passenger data and detect suspicious travel patterns. Some airports employ behavioural detection officers, trained to spot nervous or evasive behaviour. While these technologies promise efficiency, they have also sparked debates on privacy and surveillance. Civil liberties groups argue that the balance has tilted heavily toward security at the expense of individual rights.

Major changes in US airport security after 25 years?

While major countries are coming up with different and advanced ways to tighten their security at airports, the US is coming up with a new policy that is restoring some previously banned travel practices after 25 years. In response, the Transportation Security Administration (TSA) announced to allow people without tickets to pass through security and go to airport gates with loved ones.

The TSA is also weighing whether to let some US passengers carry full water bottles through security, a move that would reverse a policy put in place after a foiled terror plot in 2006. According to an aviation expert, these changes mark some of the most significant shifts in aviation security in decades and are likely the result of advances in technology rather than any relaxing of safety standards.