My opinion is that this is brilliant letter, and I fully agree with what she said. Despite the fact that her acts were illegal according to written law, I think she had good intentions and wanted to do "the right" thing. While I don't agree with how the information was leaked (both the manner and the method) I do think the American people deserve to know what was occurring and it's appears no one was harmed because of the leaks. Therefore, I hope to see her receive a pardon and hope others who believe so will speak up to the proper authority.
If you also believe in this case, I suggest you contact your representatives about whistleblower reform, so we can avoid this sort of debate in the future by making sure the proper channels are functional.
P.S. I'm happy that she quoted Zinn, as he was a childhood hero of mine. Yes, I know I am a radical left hippie, but I love all my conservative and right wing friends here too.