Are there any realistic steps an American citizen and resident can take to protect themselves against the kinds of perils that (rightly) concern you?
I don't need huge gains at this point in my life. I need confidence that I won't lose everything,?

Sort of OT, but still "out":
I've taken a quick look at visa programs for U.S. citizens wishing to live abroad. Most seem oriented toward people planning to work. I'm retired, have acquired some level of wealth over the years, so therefore looked at so-called Golden Visa programs. Requirements for me, and perhaps similar U.S. retirees, are (1) stable country (2) English as primary language or fairly prevalent as a second language (3) excellent health care (4) a place I'd enjoy living. Many countries, e.g. Canada, have eliminated 'Golden Visas' that simply require an investment. I initially found this surprising, but digging further shows the reason to be that these countries are experiencing a housing shortage and don't welcome foreigners soaking up existing housing stock.
Maybe buying a house isn't necessary, perhaps renting?
Maybe staying 180 days one country, 180 days another?
I've looked at the 'living abroad' board, didn't see much info for the 'relatively wealthy retiree' demographic.
By the way, living abroad is not a decision to be taken lightly. I have in the past, so am familiar with the necessity of an American being able to accommodate to another culture, and enjoy the accommodation!
Any suggestions?