The sensational leak shows that Blair had given an unqualified pledge to sign up to the conflict a year before the invasion started.
It flies in the face of the Prime Minister’s public claims at the time that he was seeking a diplomatic solution to the crisis.
He told voters: ‘We’re not proposing military action’ — in direct contrast to what the secret email now reveals.
The classified document also discloses that Blair agreed to act as a glorified spin doctor for the President by presenting ‘public affairs lines’ to convince a sceptical public that Saddam had Weapons of Mass Destruction — when none existed.
In return, the President would flatter Blair’s ego and give the impression that Britain was not America’s poodle but an equal partner in the ‘special relationship’.
The damning memo, from Secretary of State Colin Powell to President George Bush, was written on March 28, 2002, a week before Bush’s famous summit with Blair at his Crawford ranch in Texas.