The PM was sipping tea at 10.30am when it was confirmed by his chief of staff Jonathan Powell that terrorists had hit London with force.
Mr Blair was given a chilling telephone briefing by Home Secretary Charles Clarke, who had just chaired a security meeting in a bomb-proof bunker under Downing Street.
Visibly-shaken, the PM went back to finish a session with G8 leaders but left early to make a live TV statement, vowing never to surrender to terrorists.
The contrast with President Bush’s reaction to the news about the September 11 attacks could not have been more stark.
After planes slammed into the twin towers the world saw an aide whisper the news to Mr Bush who reacted with wide-eyed panic.
The President was bundled on to his jet and kept away from Washington and New York while Vice-President Dick Cheney took shelter in a secret bunker.
But yesterday Mr Blair was strong and defiant and flew back to London to take charge of the crisis.
I especially like the “bundled on his jet” part. Where he showed resolve, of course.
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