Un-American

[Mad Professor]

I realise most dwellars are from the US, so thought I'd put this one out.

Does the phrase "Un-American" still have any currency in the States, and if so what does it mean to you? Here in the UK we have become progressively more ethnically and culturally diverse, such that we are now having debates about what it is to be British, and we're having something of a national identity crisis. But we have never as far as I know used terms like "Un-British". Do many people in the States hold a strong sense of national identity/pride, or hold a set of principles which would lead to calling someone or something "Un-American" for whatever reason?