un-American

adjective3

1. •
   Contrary to the principles, institutions or interests of the United States; anti-American.

   • Besides, how can you talk about church politics? It would certainly be anti-Catholic and might easily become un-American. — 1948
2. •
   (US, informal) Incivil, immoral.
3. •
   Unrelated to America or the U.S.; untypical of U.S. mores or habits; non-American, not American.

   • [About British filmmaker Alfred Hitchcock:] It’s not often addressed in criticism, but Hitchcock was un-American enough to dwell on the uneasiness or the unreliability of heroes. — 2017