Former White House official tweets gripping play-by-play of what it was like to be with Bush on 9/11

"Where were you on September 11th, 2001?"

Each year, Ari Fleischer, the former press secretary to George W. Bush, tweets a gripping play-by-play account of the 9/11 terror attacks. His tweets focus on the president at the time, and those closest around him.

This year, Fleischer's tweets seemed to especially focus on illuminating exactly what happened in the Florida elementary school where Bush first learned of the attacks.

The tweets are full of details on how the president operates during a crisis. In 2001, this meant no smartphones. It also meant that even Air Force One didn't reliably have TV reception while flying.

The account gives the backstory to the chilling moment when on live TV, Bush learned the true extent of the attacks.

After learning of the attacks, Bush went to "the hold," or a room set up with secure lines for the president to receive intelligence and conference with his aides.

Fleischer tweeted that the Secret Service wanted to leave immediately, but because there were no threats in Sarasota, Florida, a visibly shaken Bush took time to address the nation about an "apparent terrorist attack on our country."

Then, the president rushed onto Air Force One. But in the motorcade on the way there, he was told of the attack on the Pentagon.

During this time, Bush was constantly on the phone with his top advisers, like former Secretary of State Condoleezza Rice and Vice President Dick Cheney.

 Immediately, Bush set about getting to the bottom of the attack.

As the president and his men flew toward Washington, the South Tower of the World Trade Center collapsed. Secret Service agents secured Bush's family. Flight 93 crashed in a field in Pennsylvania. 

The paranoia reached a fever pitch when Bush turned to the military aide in charge of the nuclear football, the portable briefcase that travels with the president at all times and can launch a nuclear strike, and said that a call came in saying "Angel" is next. "Angel" is the code name for Air Force One.

Top Bush aides feared a coordinated attack, perhaps using biological weapons, to "decapitate" the administration:

In the end, Fleischer gave all credit to Bush, the Secret Service, and the military for their service on that day. His annual recollection of the event serves as a keen reminder of how trying it was.