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Things about 9/11 that still don't make sense -

This event has been researched and documented from seemingly every possible angle for the past 20-plus years, and yet there are still some parts of the tragedy that remain unknown or debated.

Intrigued? Click through this gallery to discover the questions about that fateful day that remain unanswered.

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Airport security -

Before 9/11, airport security was shockingly lax, allowing hijackers to easily exploit weaknesses. Knives were allowed on flights, no IDs or boarding passes were required, and only basic metal detectors were used, despite previous hijackings that should have prompted stricter regulations.

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Security hesitancy -

While previous hijackings prompted some changes in security, airports remained hesitant to implement strict measures, fearing they would scare away travelers. Security was designed to be almost invisible, which led to vulnerabilities that the 9/11 attackers exploited.

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Early warnings -

The CIA was aware that an attack on US soil was imminent months before 9/11. They had intelligence that pointed to a major strike, but their warnings were ignored. A notable warning in August 2001, titled "Bin Laden Determined to Strike in US," was dismissed by the administration.

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Dismissal -

Despite the CIA's efforts, their warnings were not heeded by the Bush administration, possibly due to overconfidence. Officials believed they were adequately handling the situation, while the CIA alerts were treated as background noise.

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Miscommunication -

The failure to prevent 9/11 was partially due to miscommunication and bureaucratic mismanagement among US intelligence agencies. The CIA and FBI had different focuses and lacked a central coordinating body to share information effectively.

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Disjointed intelligence -

At the time, the CIA was focused on international threats alone, which left them blind to domestic risks. In the meantime, the FBI lacked the means to assess the danger posed by foreign terrorist groups.

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NORAD's response -

The North American Aerospace Defense Command (NORAD) was tasked with defending US airspace, yet it failed to intercept any of the hijacked planes. Many questions have arisen as to how such a highly coordinated attack went undetected by one of the world’s most sophisticated defense systems.

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Radical groups -

Domestically, law enforcement allowed radical groups to operate within the US largely unchecked before 9/11. Existing laws could have shut down these groups, but prosecutors often considered such cases not worth the effort, leading to growing threats within the country.

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Domestic terrorism threats -

US intelligence had long known about domestic terrorism risks but failed to address them. Reports dating back decades revealed that the country was ill-prepared to handle such attacks, yet little was done to enact or enforce policies that could prevent such threats.

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Flight 93 -

Flight 93, the fourth plane hijacked on 9/11, is known for crashing in Pennsylvania after passengers tried to retake control. Its intended target was likely the US Capitol, though Osama bin Laden had originally preferred to attack the White House.

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Heroic actions -

The actions of Flight 93's passengers, who stormed the cockpit after learning of the other attacks, have become a symbol of heroism. Their efforts prevented further destruction, though the exact target still remains a matter of investigation and speculation.

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Intervention -

Many others have debated whether Flight 93 was deliberately shot down by the US military. The wide debris field and the initial ambiguity surrounding military orders that day have created much speculation about the true nature of the crash.

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Health consequences -

The health consequences of first responders at the World Trade Center on 9/11 have also been heavily debated. First responders have suffered long-term health issues, including cancer, respiratory diseases, and PTSD.

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Cognitive decline - Cognitive decline among 9/11 first responders is becoming increasingly common decades later. Research indicates that many responders, now in their fifties, show brain deterioration typical of individuals much older, including severe cases of dementia.

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Toxic dust -

A Stony Brook University study from 2014 to 2023 confirmed a correlation between toxic dust exposure at the World Trade Center and the development of dementia among first responders. The study is a starting point for understanding these conditions, but more research is needed.

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The use of torture -

In the wake of 9/11, American intelligence agencies engaged in torture at Guantanamo Bay and other secret prisons, using methods like waterboarding and sleep deprivation. These practices, often ineffective, have left lasting trauma on prisoners and violated international human rights laws.

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Ineffectiveness -

The torture carried out by US officials post-9/11 did little to provide useful intelligence and instead damaged the country's reputation. By declaring the prisoners "unlawful enemy combatants," the Bush administration was able to bypass the Geneva Conventions, sparking global controversy.

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Human rights violations -

Despite efforts to close Guantanamo Bay, the prison remains open. The use of torture by the CIA has stained the US' global standing, with human rights organizations still unable to fully receive answers for the abuses that occurred.

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Delayed trials -

Over two decades after 9/11, key figures accused of orchestrating the attacks have yet to stand trial. Five men charged with planning the attacks have been held since the early 2000s, but their cases have faced numerous legal and logistical delays.

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Legal complications -

The trial process for 9/11 suspects has been delayed by numerous factors, including the inadmissibility of evidence obtained through torture. President Barack Obama's attempt to move one trial to federal court was blocked, and military tribunals have proven controversial.

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Pandemic -

Attempts to prosecute 9/11 suspects were further stalled by the COVID-19 pandemic, which delayed jury selection and pretrial hearings. As of 2024, plea deals have fallen through, and the already complicated legal proceedings have been prolonged even further.

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Omar al-Bayoumi -

One of the lingering mysteries of 9/11 is the role of Omar al-Bayoumi, a Saudi national who helped two hijackers find housing in California. Though evidence suggests he may have known about the attacks, his exact involvement remains unclear.

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Ties to Saudi intelligence -

Speculation surrounds Omar al-Bayoumi's connections to Saudi intelligence. Some believe he was a paid informant, while others (including families of 9/11 victims) have accused the Saudi government of financing the attacks. No official ties have been confirmed.

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Transparency -

In the decades since 9/11, calls for transparency regarding Saudi Arabia's potential involvement have grown. Some documents related to the attacks remain heavily redacted, fueling theories that the US government may be protecting its ally from scrutiny.

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Delay in declassifying documents -

The delay in declassifying 9/11-related documents has sparked speculation about why the information was hidden in the first place. Some theorize it is to protect Saudi Arabia, a key US ally, though the Saudi government has denied involvement and supports declassification.

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Financial transactions -

Prior to the 9/11 attacks, there was a surge in financial transactions that some have interpreted as insider trading, speculating that certain individuals may have had foreknowledge of the attacks. Investigations into these financial activities have been inconclusive, but many questions still remain.

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Building 7 collapse -

One of the most perplexing questions revolves around the collapse of World Trade Center Building 7 (WTC 7). Unlike the Twin Towers, it was not directly hit by planes but collapsed hours after the main attacks.

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Official explanation -

The official explanation for Building 7’s collapse cites fire-induced structural failure, but skeptics question the sudden, symmetrical nature of its collapse, and have compared it to controlled demolitions.

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Perception of safety -

The public perception of safety was drastically changed due to 9/11. To this day, psychologists are still unravelling the unknown impact that the event had in civilians, and how it has shaped a more security-conscious world.

Sources: (Grunge) (BBC) (The Washington Post) (National September 11 Memorial & Museum)

See also: Secret messages hidden in famous statues

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