In 2003, Katharine Gun made a decision that would change the course of the reasoning behind why the United States invaded Iraq. As a translator at the UK's Government Communications Headquarters, Gun leaked a top secret memo revealing that the United States was plotting a spy operation on the United Nations in exchange for authorization to invade Iraq.

Gun joined "Salon Talks" to discuss why she chose to expose the memo, what she thinks of today's whistleblowers, and the new Hollywood film based on her story, "Official Secrets," out in theaters August 30 and starring Keira Knightley and Ralph Fiennes.

In order to obtain legitimacy for launching the Iraq War at the time, Tony Blair and the Bush administration were desperate to get UN cover. "Leaking the memo essentially blew that up in their faces," Gun said. The allies were forced to take another route-proving that Iraq had weapons of mass destruction.

While describing her immediate thoughts after receiving the revealing memo in her email, Gun recalled, "I really felt that time was absolutely pressing, that there was no time to take it up to any of my superiors," she said. "I felt they would just sweep it under the rug and they would just keep extra special eye on me."

Gun then mailed the memo to a contact in the antiwar movement. It was exposed to the world in a story published by The Observer. Gun admits that she did not enjoy the limelight. "I was actually quite traumatized by the whole thing," she said. "At the end, I just wanted to disappear back into anonymity."

When it comes to today whistleblowers like Edward Snowden and Julian Assange, Gun calls them smart, but is also quick to distinguish her case from theirs. "I think those guys, it's a philosophical argument. It's about whether the degree of transparency that we should expect from our governments and so on. I think that's a whole different topic." Watch the episode above to learn more about Keira Knightley's portrayal of Gun in the movie version.