I was driving to work when the first plane struck. The radio, set to the local National Public Radio station, reported a scene from a disaster movie as American Airlines Flight 11 impacted the North Tower of the World Trade Center complex in New York City.

Only this wasn’t a disaster movie.

Seventeen minutes later, my coworkers and I stood in the cafeteria and watched in horror as United Airlines Flight 175 slammed into the South Tower. Thirty-four minutes after that, American Airlines Flight 77 took aim at the Pentagon. A fourth attack was averted by the passengers of United Airlines Flight 93.

Less than two hours later, both WTC1 and WTC2 were piles of rubble, and 2,751 confirmed victims and 19 al-Qaeda terrorists died in the destruction. It was, and remains, the deadliest attack by extremists in history. When the dust finally settled, we learned that 2,977 people died that day. This number does not begin to include those whose lives were otherwise affected by the assaults. Hundreds of rescue workers and residents of the area have been diagnosed with cancer — caused by “Ground Zero toxins.” Many more have died of that toxin exposure since.

The aftermath changed America.

We stand in remembrance of a day that changed the course of history, another day that will live in infamy.