The Hijackers Debated: Hit Only One WTC Tower, Target White House Instead?

In this series, Newsweek maps the road to 9/11 as it happened 20 years ago, day by day.

Mohammed Atta in the U.S. and Ramzi bin al-Shibh in Berlin discussed the prospective targets of attack on August 19. Bin al-Shibh talked about the conversation in his interrogations and debriefings at Guantanamo, and Donald Rumsfeld wrote in his memoir, "Known and Unknown," that the two spoke "in a code in which they pretended to be students talking about various academic fields."

In their conversation, Rumsfeld says, "architecture" meant the World Trade Center, "arts" referred to the Pentagon, "law" to the U.S. Capitol building, and "politics" to the White House.

From the beginning in 1999 when the Hamburg four were given their assignment to undertake the planes operation, Al Qaeda central wanted the attackers to hit one political, one military and one financial target. In Afghanistan, those three were originally set as the White House, the Pentagon, and the World Trade Center. Osama bin Laden personally wanted the U.S. Capitol dome to be hit, telling Atta that the Congress was the center of American support for Israel.

As Khalid Sheikh Mohammed would later tell the CIA, ultimately the decision rested with Atta, based on the conditions on the ground. With four pilots, it would be possible to hit all four at once in the United States, Atta and Marwan al-Shehhi visited the World Trade Center and Washington DC, even taking a Pentagon tour. Atta determined that the White House was the most difficult target, that the Presidential mansion was smaller than he imagined and was tucked in between two larger buildings (the Treasury Department and the Eisenhower Old Executive Office Building). The other targets, in contrast, were large and wide open.

At some point, according to KSM's recounting and the view of FBI agents who reconstructed the events leading up to 9/11, Atta and Marwan al-Shehhi decided that they wanted to die together, that they would hit both towers nearly simultaneously, while the Washington targets would be struck thereafter in quick succession. Hani Hanjour, on a plane leaving from Dulles International Airport, would hit the Pentagon, and Ziad Jarrah, on a flight leaving from Newark, would hit the Capitol dome.

It is not clear that Atta frankly passed on his plans to al Qaeda, but bin al-Shibh pressed Atta to retain the White House as a target in the August conversation and Atta agreed, still saying that the White House might prove impossible, based on his scouting.

Why does any of it matter, about where al Qaeda intended to strike versus where the pilot ultimately did? For one thing, it is now clear that attacks on both Trade Center buildings were integral to their collapsing. The resulting dispersal of fuel and debris, and the intense heat created, accumulated to cause both buildings to fall. Engineers who have studied the effect believe that had only one building been hit, it might have survived. Further evidence of the cumulative impact is seen in the nearby 7 World Trade Center, a building that wasn't even directly attacked but also collapsed on 9/11 as a result of the cascading heat and flying debris. In other words, if things had gone according to al Qaeda's plan, the Trade Center complex might have survived.

And had Atta and al-Shehhi followed al Qaeda's plan, the White House might also have been struck. Consider what that would have meant: the ultimate symbol of America destroyed. It's hard to imagine what that aftermath would have been, but had Vice President Dick Cheney been killed, and had George W. Bush had nowhere to return to, the world today might look very different.

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