I find it troubling that some of you seem to be trying to downplay her role as a covert agent.
Let's say she's been behind a desk for 3 years, does that mean that she would never be in the field again? By blowing her cover, her usefulness as an in-field asset has been removed.
What about people who have worked with her? Let's say person A is an agent who meets with person B in some country, and person B is a mole that is giving person A info. Person A is unmasked as an agent a couple years later, so some enterprising security agent of said country decides to run some credit card receipts or go over some old records, and suddenly, lo and behold, sees the connection between person B and person A.
End result, people can die because of this stuff.
Did it happen here? I don't know.
Finally, y'all should have the same reaction to the unmasking of an agent without regard to whether it was a democrat, republican, or martian that did it. I feel that some of the people responding would not do so the same way if it was, say, Senator Kennedy. This is not a republibasher sentiment, I think there are some liberal folks that might be chomping at the bit more then usual, but I also think some of you conservative types are being... uncharacteristically unconcerned.
Ideally, this should not be a partisan issue, it should be a 'protection of the nation' one that goes beyond political one-upsmanship.