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America’s transportation system dramatically changed as a result of the Sept. 11, 2001, attacks, when four commercial jets were hijacked and crashed, killing nearly 3,000 people.
“The building has exploded right now. You have people running up the street. Everyone is panicking,” an eyewitness told a reporter moments after the second World Trade Center tower was struck.
President George W. Bush was attending an education event in Sarasota, Florida, and addressed the nation.
“Terrorism against our nation will not stand,” Bush said.
In less than two hours, hijacked aircraft struck both World Trade Center towers in New York, the Pentagon outside Washington and a field near Shanksville, Pennsylvania. The towers later collapsed after the impacts and resulting fires.
About 51 minutes after the second tower was struck, American Airlines Flight 77 crashed into the Pentagon. Less than an hour later, United Airlines Flight 93 crashed near Shanksville after passengers fought back against the hijackers, who investigators believe intended to fly the aircraft toward Washington.
Within hours, the Federal Aviation Administration ordered the first nationwide grounding of commercial aviation in U.S. history. More than 4,500 aircraft were forced to land, stranding hundreds of thousands of travelers and bringing the nation’s air transportation system to a halt.
“The landing of those aircraft stands as the single greatest feat in all of ATC history,” said former National Air Traffic Controllers Association President John Carr.
The nation’s airspace remained largely closed to commercial traffic for more than 49 hours. Cargo pilot John Kramer of Atlanta was among the first pilots allowed back into the air, flying freight from Augusta, Georgia, to Hartsfield-Jackson Atlanta International Airport. The world’s busiest airport was eerily quiet.
“As I approached Hartsfield, I was totally stunned by the silence on the radio as I talked to the tower,” Kramer recalled. “He cleared me any runway, any speed, which I had never heard in my years of flying into that giant airport. I was the only airplane cleared.”
Before Sept. 11, airline travel was markedly different. Passengers could arrive at airports minutes before departure. Family members routinely accompanied travelers to departure gates. Screening was conducted by private contractors and cockpit doors offered limited protection.
In response to the attacks, Congress passed the Aviation and Transportation Security Act. It created the Transportation Security Administration, federalized passenger screening and established new security standards throughout the transportation system.
Airports soon introduced extensive passenger screening, explosive detection systems for checked baggage and restrictions on liquids carried aboard aircraft. Airlines were required to install reinforced cockpit doors, while the Federal Air Marshal program expanded dramatically.
In an address to the nation on Sept. 20, 2001, just nine days after the attacks, President Bush spoke to a joint session of Congress.
“So tonight, I announce the creation of a cabinet-level position reporting directly to me — the Office of Homeland Security,” Bush said.
“The 9/11 attacks bring an immediate and profound change to commercial aviation,” said a narrator in a Smithsonian Channel documentary examining the security changes that followed the attacks.
In the D.C. area, significant changes took place at Ronald Reagan Washington National Airport, where airspace restrictions around the airport, the White House, the National Mall and other landmarks were tightened dramatically.
Most general aviation operations were prohibited at Reagan National and shifted to surrounding airports. Pilots who wish to operate within the D.C.-area Special Flight Rules Area must complete FAA training and testing on the complex security procedures that remain in place today.
But the changes extended far beyond aviation.
Access controls increased at ports, rail systems, transit networks and trucking facilities. The newly created Department of Homeland Security coordinated transportation security efforts nationwide, fundamentally altering how Americans move through the transportation network.
Congress has spent billions of dollars hardening security at the nation’s ports, rail facilities and other transportation hubs to prevent potentially dangerous cargo and materials from entering the United States.
Since 9/11, the federal government has invested tens of billions of dollars in airport screening, cargo inspection systems, port security, rail and transit protection and other homeland security initiatives designed to safeguard the nation’s transportation network.
At the Port of Baltimore, security measures adopted after 9/11 include radiation detection systems that screen cargo containers and trucks for nuclear or radiological materials before they enter the supply chain. Ships are required to provide detailed information before arriving in port and cargo is subject to risk-based screening and inspection by federal authorities. Similar security measures have been implemented at major ports across the country.
“People think of airport security, which totally changed, but we have rail systems, ports, trucking, all that changed, particularly our ports, where there’s a lot of resources, a lot of pretty sophisticated technology being used,” said DePaul University transportation professor Joe Schwieterman. “But it added a real constraint that slowed things down a bit and really required a whole new supply chain reorientation.”
The changes were also felt beyond transportation. Prior to 9/11, routine airport-style security screening was uncommon at sporting events, concerts and many other public gatherings.
“This really was a tidal wave of change,” Schwieterman said.
Twenty-five years later, travelers still encounter many of the security measures put in place after Sept. 11. From airport checkpoints and reinforced cockpit doors to expanded protections at ports, rail systems and transit networks, the attacks permanently reshaped how Americans move people and goods throughout the nation.
The attacks transformed not only how the nation protects itself, but also how Americans travel, fundamentally reshaping transportation for generations.
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