Welcome to Hard Talk on the BBC World Service with me, Stephen Sacker.

My guest today underwent one of the most remarkable ideological conversions in post-World War II America.

Daniel Ellsberg was a Harvard-trained economist who served in the U.S. military.

He worked as an analyst at the influential Rand Corporation. He advised the

Pentagon on nuclear strategy. He was a defense hawk who in the early years of U.S. involvement

in Vietnam supported military intervention. But all of that changed after he made his own

visit to the front lines as an analyst. He became convinced that

this was a war America couldn't win. In his role at the Rand Corporation, he had access to a

storehouse of secret documents known as the Pentagon Papers, cataloging decades of lies and

deception concerning Vietnam perpetrated by successive administrations in Washington.

In 1971, he leaked them to the New York Times and other newspapers.

Ellsberg was put on trial, but not only that, a CIA operation was mounted to discredit and destroy him. It was a plot that

foreshadowed Watergate, and in the end, it was President Nixon's reputation, not Ellsberg's, that

was destroyed. After his trial collapsed, Ellsberg devoted his life to the campaign for transparency

in government.

He's been a public supporter of Chelsea Manning, Julian Assange and Edward Snowden.

He even released more confidential material about America's nuclear strategy going back to the 1950s.

His warnings have been long and loud.

But has America been listening? Well, Daniel Ellsberg joins me now in his beautiful California garden. Daniel Ellsberg, welcome to Hard Talk.

Glad to be with you. Now, you have lived a long and a very full life, and I guess the truth is you know that you will always be associated with one extraordinary decision you took to leak the Pentagon papers.

Does it bother you that that is the thing that people think about you.

No, well, I know that it is, but so I've lived with that for a long time.

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