I've got no particular clue. But if the plan is to assume things happen slowly over 50 years then that is a risky plan. If things play out like in the 1900s, we could see an entire world war play out over 5 years and that'd likely break the US dollar. Or some similar shock. We still don't really understand the impacts of the COVID pandemic and what that is doing in China.

> Money in mattress?

The response to every crisis the US has had for the last 3 decades is to print and borrow increasingly large amounts money. And they are probably the most responsible fiscal controller around at the moment.

If you see that changing for some reason then sure, maybe money under the mattress could help. I don't expect that strategy to change myself, and the last thing I'd want under my mattress is money.

> People should have contingencies ready in case something unprecedented happens.

> What kind of contingencies? Money in mattress?

The right to live in multiple countries on a permanent basis (foreign permanent residence and/or passports) and investments that automatically balance as world markets shift over time (e.g. the worldwide equivalent of VTI: VT)