Alongside the thousands of Americans killed on 9/11, dozens of Europeans lost their lives that day — and 25 years on, some of the people accused of being behind the attacks have still not faced justice.

Many things have changed in the world of public opinion since the Sept. 11, 2001, terrorist attacks in New York City.

After 25 years, 100 million Americans have no memory of the day that changed everything. In an age of social media, disinformation and mistrust, that can be dangerous.

The 2001 attacks unfolded across New York, Virginia, and Pennsylvania, killing nearly 3,000 people and permanently changing American life.