When she was exposed two years ago, it led to a federal investigation and raised questions about what would motivate such a betrayal. Would someone in the government go that far, leak her name to the press, in retaliation for her husband's public criticism of the war in Iraq?
The special prosecutor in the case, Patrick Fitzgerald, did not answer that question on Friday when he charged the vice president's Chief of Staff Lewis Libby with lying to the investigators who were trying to find out how it could have happened.
But 60 Minutes wanted to know how serious was the damage done by the leak.
The woman at the center isn't talking. But 60 Minutes Correspondent Ed Bradley did hear from her husband, her friends and fellow agents who knew her work, and helped us understand what happens when an agent for the CIA is exposed.
"It's a spy agency. And you don't expose people working for a spy agency. And no one knew that she was working for a spy agency until she was exposed," says Jim Marcinkowski, a deputy city attorney in Royal Oak, Mich. In the late 1980's, he was a covert CIA agent spying in Central America. Like all recruits, he was sent to the agency's top-secret training facility in Virginia known simply as "the farm."
That's where he first met a 22-year-old graduate of Penn State University named Valerie. Marcinkowski says he knew her simply as Val P., since recruits went by the initial of their last name. And he says she was a natural.
"Did all of you have firearms training?" Bradley asked. "Yes," he replied.
Marcinkowski says she was good. "Some people had never fired weapons before, and some of us had. And it's always interesting when someone that has never fired a weapon kind of beats everybody else that did."
He says the three dozen members of his CIA class were a close-knit group that continued to see each other at class reunions.
Two years ago, when columnist Robert Novak put the name "Valerie Plame" into the public debate over the war in Iraq, Marcinkowski says it took him a few weeks to determine that it was "Val P." who had been compromised. "I found that particularly outrageous. It became very personal."
Marcinkowski was so angry, he went public, something former CIA agents rarely do, blaming the White House, even though nobody has been charged with the actual leak.
"We kept that trust in protecting her identity. So we held a particular trust for 18 years and never gave each other up. And when the White House did that, it was particularly outrageous, because if I have to keep those secrets, they should be held to that same kind of standard," he explains.
As the investigation into who leaked her name got underway in Washington, more details about Valerie Plame's life emerged. She spent her early years in the CIA in Europe, where she received advanced degrees from the London School of Economics and the College of Europe, in Bruges, Belgium.
In recent years, she told people she worked at an energy consulting firm called "Brewster-Jennings & Associates."
Robert Novak, the columnist who first printed her name, revealed that, too. "And she listed herself as an employee of Brewster-Jennings & Associates. There is no such firm, I'm convinced," Novak said on CNN.
He was right. Even though the business directory Dun & Bradstreet had a listing for the firm in a Boston office building, Brewster-Jennings & Associates was a CIA fiction, created to provide cover for agents like Valerie Plame.
The problem, says Marcinkowski, is that exposing Brewster-Jennings could lead foreign intelligence agencies to other spies. "There is a possibility that there were other agents that would use that same kind of a cover. So they may have been using Brewster-Jennings just like her."