
Living overseas, I’d say your biggest worry should be the strength of the US dollar - strong dollar, lots of local currency; weak dollar, less local currency.
The dollar gets a lot of its historical strength from the combination of big country untouched by wartime destruction and being the global reserve currency. Being the reserve currency is a huge but hard to quantify factor, because it means that every major agent on the planet buys dollars, even if they don’t want to buy or sell goods in the US. It’s the reason the dollar gets stronger during global crises. China and Russia have tried for years to shake that reserve currency status and get the world to shift to something else for denominating international deals. Basket of BRIC currencies. Renminbi. Even Euros. Current administration’s isolationism may help those efforts, but it would be an enormous international reconfiguration to make that big a change, and isn’t likely to happen because of one four-year administration.
US inflation will tend to devalue the dollar - inflation and exchange rate are kind-of correlated, over relatively short time periods, but economic growth is more important over the long term.
If you make it to Medicare age, it gets a lot less stressful. eg: my folks have had 4 knees replaced with very little out-of-pocket cost. There’s still supplemental insurance, but Medicare, not the profit-driven insurance company, determines what gets covered, and they mostly listen to doctors. There’s always edge cases, where some treatment might not be covered, but I feel like those are uncommon.
One way or the other, my ultimate health care plan is 9mm.