DHAKA: In the 14 years since the 9/11 attacks, the face of terrorism has changed out of recognition. To many experts, the threat of Islamist terror is in some ways greater and in some ways diminished.

It is geographically more diverse and organizationally more divided, and leverages social media and the internet in a way impossible in 2001, reports CNN.

In the West, Islamist terrorism is often more inspired than organized and directed.

Its menace is also more fluid and unpredictable than it was on that bright autumn morning in 2001, but the tools to combat it are also more plentiful, from ever more sophisticated and accurate drones to financial intelligence and algorithms for chewing terabytes of data in the pursuit of suspicious communications.

The likelihood of an attack on the scale of 9/11 has receded. but the probability of more frequent though less devastating attacks has increased.

America remembers lives lost

Bells will toll and tears will flow as the nation marks a dark day in sorrowful yet hopeful ceremonies.

Fourteen years ago today, terrorists hijacked passenger planes and rammed two into New York City's World Trade Center, and a third one into the Pentagon in Washington.

A fourth jetliner crash-landed on an empty field in Pennsylvania.

By the time the carnage was over, terrorists had killed 2,977 people in one of the deadliest attacks on American soil.

People, buildings and planes fell from the sky. Terrified strangers became friends as Americans united on a day that changed the world forever.

Today, like every other anniversary after it happened , a resilient nation will look forward to the future, but remember the past.

BDST: 1625 HRS, SEP 11, 2015
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