The journalist's journalist." A fitting epithet from Nick Clarke, the voice of Radio 4's The World At One, in conversation with Pulitzer prize-winner Seymour Hersh, who is best known for exposing the My Lai massacre during the Vietnam War.

Beginning with a brief mention of Hersh's early investigative pieces, which share the common theme of exposing the dark underbelly of the American political elite, Wednesday night's proceedings departed from more recent events.

Clearly a man who retains the energy which has driven him to uncover some of the most heinous scandals, the conversation largely revolved around Bush's presidency and America's relationship with the Middle East.

The invasion of Iraq, US prisons in Guantanamo Bay and Afghanistan, America's stance toward Iran and the fragility of the Middle East were some of the issues discussed, occasionally interrupted with sagacious musings about the role of the reporter in our society.

A strong and opinionated voice was expected from the man whose investigations have probed the recesses of American power.

Affable, down-to-earth and at times amusing, Hersh's American optimism coupled with the more journalistic pessimism proved his ability as a speaker as well as a writer.

His most recent investigative pieces about the events leading up to the US-led invasion of Iraq were quizzed and queried by Nick Clarke and questions from the floor focused on the current political geography of the US and its involvement with Iraq.

This was a shame, considering the sheer breadth and span of this man's journalistic career. More about his life and his reportage in general would have been a more rewarding experience but, nevertheless, hearing Hersh speak gave a valuable insight into the mind of a hugely influential and dedicated reporter.