No, she's going to jail for 26 years because she was found guilty of murder by a legitimate court of law in Italy. I don't think nationality had anything to do with it.
And her co-accused, who were also found guilty, are NOT American.
Whether or not she is actually guilty, I cant say, I cant be bothered looking for the case notes.
Now, if they can get GW, Cheney, Rumsfeld and the rest of them in front of the Hague, that'd be a huge step forward. It'll never happen though.