The time was 9:59 a.m. when the South Tower had collapsed, changing the lives of many. Sept. 11, 2001, was a day that will always be remembered by millions of Americans, whether it was witnessed first hand, watched on the television or taught during school.

“I was teaching in room 218 when our crisis counselor knocked on the door and beckoned me into the hallway,” math teacher Bradley Fischer said. “He informed me what was happening and I was in disbelief. My initial thoughts were many: How did this sort of evil get into our country? [I feel] sadness for the inevitable loss of life that day.”

As the events of 9/11 occurred, countless individuals found themselves drawn to television screens, witnessing the tragedy unfold in real-time. For many, it was an experience etched into their memories forever.

“My mom was a teacher,” senior Phinn Bitza said. “She was teaching seventh grade. She described it to me, as they had a TV that was connected to cable in her classroom at the time. They turned on the news and her entire seventh grade class had seen the second tower get hit, live.”

These sentiments echo the initial shock and confusion felt by tens of thousands of Americans as they watched the events unfold. The attacks on the World Trade Center and the Pentagon not only claimed the lives of thousands but also shook the very foundations of the nation.

“I was five years old at the time,” English teacher Dora Brewington said. “The 9/11 attacks really brought a new perspective on the amount of evil in the world. Social media wasn’t as prevalent then, so information from around the world wasn’t as accessible as it is now. It was a wake-up call, that innocent people’s lives were not always thought of as precious.”

For the younger generation, 9/11 may be a history lesson, but its impact resonates in the changes they have seen in airport security and national security measures.

“National Security changed everything,” Brewington said. “We used to be able to just board a plane and go. After [9/11], you have to go through so many security checks, everything is x-rayed. You always had to worry about people sneaking contraband into things.”

As the years have passed, the collective memory of 9/11 has evolved from a real-time tragedy to a historical event. It is a reminder that history is not static but continually unfolding.

“It’s history in real-time,” Bitza said. “We’re seeing how the largest terrorist attack on U.S. soil has grown in our history books. [We’re] learning about when Osama bin Laden was killed. It is really jaw-dropping, honestly, and to a lot of people, it feels like yesterday.”

The attacks had shattered the illusion of invulnerability on American soil. They served as a stark reminder that evil could reach even the heart of the nation. However, amidst the tragedy, a spirit of unity emerged.

“The attacks did force our country into a unified force, which was inspirational,” Fischer said. “Race, political affiliation, religion, socioeconomic status–everyone came together as a country.”