September 11, 2001 — 25 years since the attacks on the United States
The anniversary marks nearly 3,000 dead, more than $20 billion in direct damage and sweeping security and strategic changes.
On September 11, 2001, coordinated terrorist attacks against the United States changed the world’s political and security landscape and left a deep human and economic toll that is still being measured on the 25th anniversary, September 11, 2026.
The direct material damage from the attacks is estimated at more than $20 billion, while the total cost to the American economy over time grew into the hundreds of billions of dollars. Nearly 3,000 people were killed, and thousands more were wounded or later suffered serious health consequences.
Military and alliance consequences
The attacks prompted a fundamental shift in U.S. military doctrine, moving from deterrence toward a policy of preventive action—often referred to as the Bush Doctrine—and set in motion the Global War on Terror. The United States invaded Afghanistan in 2001 and, two years later, Iraq.
For the first time in NATO’s history Article 5 of the North Atlantic Treaty was invoked, and after the United States identified Al Qaeda and its bases in Afghanistan, Article 5 became fully operational on October 4, 2001, enabling allies to take direct part in military and security operations beyond the Euro-Atlantic area.
Two hijacked planes struck the twin towers of the World Trade Center in New York; the towers collapsed within two hours, destroying much of Lower Manhattan. A third plane hit the Pentagon in Arlington, Virginia. Passengers and crew on the fourth hijacked airliner resisted the attackers and forced the aircraft down in a field near Shanksville, Pennsylvania.
Photo: press material from the event
