Agudah constituents in America, Chasidim in America and Yeshivish in America as well as Agudah constituents in Israel, Chasidim in Israel and Yeshivish in Israel would all self-identify as a Chareidi/UO on a survey, if asked.
You assume. I say they would identify as Modern Orthodox, as they will be asked if they use electricity. 🙂
Chareidism is indeed an import from Israel
The term only started receiving usage (often pejoratively) in the ’90s
Probably accurate enough. No idea about the hat (or not), or if a Straimel or Spodik counts as well.