She became the American 'ambassador to' Italy [=she began representing America in Italy] several years ago.
a 'goodwill ambassador' [=a person who travels to different places to promote friendship and goodwill]
an 'ambassador' of hope [=a person who tries to bring hope to another country or group of people]
(..) You see that? If you don't handle this correctly, you do not recover from it. This is about continuity of government. Informing NATO, informing world leaders. We should have had ambassadors on call. Joint Chiefs of Staff, the National Security... Even Nixon did that! but I want to be assured (..)2017 TvShow: House of Cards Title: Chapter 65 Season: 5 Episode 13