On the occasion of the 21st anniversary of the September 11, 2001 attacks, the United States commemorated the approximately 3,000 victims. In New York, a bell rang at 8:46 a.m. in 2001, when an Islamist terrorist steered the first of a total of four hijacked planes into the North Tower of the World Trade Center. Relatives then read the names of the victims.

In addition to Mayor Eric Adams and his predecessors Bill de Blasio and Michael Bloomberg, US Vice President Kamala Harris also attended the memorial event in New York. This year, one of the relatives used the event for a special message. Addressing the politicians present, the cousin of two victims said in an emotional appeal: "It took a tragedy to unite our country back then. I would like to remind you all: It shouldn't take another tragedy to unite our nation."

During the night of Sunday, two pillars of light protruded from the ground where the World Trade Center had once stood. The famous Empire State Building was also lit up in blue to commemorate it.

Another plane crashed into the South Tower of the World Trade Center. Both towers then collapsed. The terrorists had directed a third machine to the southwestern part of the US Department of Defense near Washington. Plane number four crashed in Pennsylvania after passengers resisted the hijackers. The mastermind behind the attacks, Osama bin Laden, was killed by US special forces in 2011.

The terrorist attacks continued to claim thousands of victims well after September 11, 2001. Many of the first responders and survivors became ill from exposure to a variety of toxins in the debris field of the Twin Towers. Researchers have identified more than 60 types of cancer and about two dozen other diseases linked to the attacks over the past two decades, according to the journal Scientific American.