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9/11 What-if Scenarios

By Patrick J. Kiger Unfortunately, there’s no way to undo the tragedy of the September 11 attacks. But just as we wonder how history might have been different had Abraham Lincoln chosen not to go to Ford’s Theater on that fateful night in 1865, or what might have happened had U.S. Naval Intelligence gotten wind...

By Patrick J. Kiger

Unfortunately, there’s no way to undo the tragedy of the September 11 attacks. But just as we wonder how history might have been different had Abraham Lincoln chosen not to go to Ford’s Theater on that fateful night in 1865, or what might have happened had U.S. Naval Intelligence gotten wind of the planned attack on Pearl Harbor in 1941, it’s tantalizing—or perhaps even more heartbreaking—to contemplate what subtle but significant alternative twists might have led to a less horrific outcome. On the other hand, we also must consider the possibility that other twists could have made September 11 even more awful, hard as it is to imagine.

1. What if U.S. national security officials had anticipated that an airliner might be used as a weapon?

This perhaps is one of the most frustrating “what if” scenarios, because officials should have realized that there was a serious risk of such an attack. According to the report of the Presidential commission that investigated the 9/11 attacks, a captured terrorist revealed to authorities in the Philippines back in 1995 that his group wanted to crash a plane into Central Intelligence Agency headquarters in Langley, Virginia, and U.S. intelligence officials received information in 1998 about a supposed Libyan plot to fly a jet into the World Trade Center.

That same year, anti-terrorism officials ran a simulation exercise that envisioned terrorists filling a hijacked private jet with explosives and flying it toward Washington, D.C.  North American Aerospace Defense Command officials also considered such a scenario, but rejected it as unrealistic. But the word never was spread throughout the government, or to the private sector, that the airliner-as-a-weapon scenario was a risk. If it had, it’s conceivable that local law enforcement agencies and private flight instructors would have been on the lookout for suspicious characters who wanted to learn to fly jets, and the military would have been prepared to intercept hijacked aircraft and prevent them from reaching their targets.


On the National Geographic Channel: Inside 9/11 — War on America



2. What if U.S. immigration officials had prevented the hijackers from entering the U.S.?

It’s probably a mistake to blame immigration officials, because according to the 9/11 commission report, the real problem here was the U.S. intelligence bureaucracy and its shortcomings in sharing and acting upon information. In January 2000, for example, the National Security Agency intercepted communications in Asia suggesting that two subjects named “Nawaf”and “Khalid” were members of  some sort of terrorist cadre. Had NSA analysts sifted through their databases, they might have identified the two as known Al Qaeda operative Khalid Sheikh Mohammed and Nawaf al Hazmi, one of the hijackers. Had that and other crucial information reached the right officials, Hazmi might have been prevented from entering the U.S., or arrested when he arrived.

3. What if the hijackers’ box-cutters had been detected and stopped by airport security?

This is another painful “what if,” because several of them were nearly caught.  According to the 9/11 commission report, when hijackers  Majed Moqed and Nawaf al Hazmi passed through security at Dulles airport in Virginia on the morning of 9/11, both men set off the metal detector. But after being screened with wands, they were allowed to board American Airlines Flight 77. According to the report, an expert who later reviewed the videotape of the wand screening found that it was “marginal at best,” and that the cause of the alarm was never verified.

4. What if the airliner cockpits had been hardened against intruders?

Long before 9/11, Israel’s El Al airline retrofitted the cockpits of its U.S.-made aircraft with armored doors that were virtually impregnable from the outside, and made it standard procedure to keep the doors locked at all times during flights, according to this 2001 New York Daily News article. But U.S. airlines resisted such security measures as too expensive, according to the 9/11 commission report. To make matters worse, the Federal Aviation Administration instructed pilots not to resist hijackers and to accede to their demands while in the air. Had the hijackers been unable to get to the aircrafts’ controls, that would have prevented them from redirecting them and crashing them into their targets.

5. What if armed air marshals had been on board the planes to confront the hijackers, or crew members had been trained in self-defense?

The 9/11 commission report noted that on 9/11, federal officials had just 33 armed and trained air marshals at their disposal, and that they generally weren’t utilized on domestic airline flights.  Since the attacks, the number of marshals has been greatly increased—a federal official said in a 2008 CNN story that the number was “four digits,” and that they fly on “thousands” of flights per day.  (On the other hand, CNN, which surveyed pilots and crews, estimated that marshals were present on only about one percent of the 28,000 airline flights each day.) Time magazine reported in 2004 that the guards are equipped with SIG Sauer pistols loaded with hollow-point projectiles and are trained in hand-to-hand combat.

It’s conceivable that if each of the four planes had been lucky enough to have an armed air marshal aboard, he or she might at least have prevented the attackers from reaching the cockpit.  It’s harder to say whether the crew members could have been much help. The Transportation Safety Administration now also provides a voluntary one-day self-defense training class to airline crews, but defending against an attacker armed with a knife or box-cutter takes considerably more martial arts skill.

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Meet the Author

David Max Braun
More than forty years in U.S., UK, and South African media gives David Max Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. In his 22-year career at National Geographic he was VP and editor in chief of National Geographic Digital Media, and the founding editor of the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directed the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. A regular expert on National Geographic Expeditions, David also lectures on storytelling for impact. He has 120,000 followers on social media: Facebook  Twitter  LinkedIn