This is somewhat amusing to me as I've been saying these things for years and obviously I was far from the first to make these observations. I've covered this ground many times so without repeating the entire thread I believe the loss of dollar hegemony will not be a disastrous train wreck but more of what we have seen; the dollar today is less important than it was five years ago. Many transactions between other countries that used to be conducted in US dollars are now being done directly. The fundamentals backing the US dollar have certainly changed which makes the dollar less attractive by some magnitude. You can decide for yourself what the magnitude is but I think it will be far more gradual of a thing because despite the state of the USD and economy the US is still a very wealthy country (wealth gaps notwithstanding) and many countries rely on us to buy stuff from them and while consumption and income numbers may still tweak at the margin we are still buying a lot of stuff.
Even though this is not apocalyptic I do believe in investing extensively in foreign denominated assets. For the most part we own foreign stocks and short dated foreign sovereign debt. In the past we've done more with currency ETFs and could use them again.
The Barron's interview had a lot of comments from Ray Dalio on this topic. One snippet from him;
I believe that sometime in the next 18 months, we will probably have a seismic shift, very similar to the Bretton Woods breakup in 1971, in which linked monetary policies and linked exchange-rate policies come undone. The pain of holding them together is going to be terrible, and that's going to create the seismic shift.
He generally prefers currency from creditor countries (as opposed to debtor nations) and emerging market currencies.
The currency article is quite clear that this doesn't have to be about becoming an active currency trader looking to scalp a few pips every hour. I think for people not so concerned about being very right about a single currency the two WisdomTree basket ETFs can work. One owns emerging market currencies and has symbol CEW (I own a few shares of that one) and the other owns currencies from commodity based economies and has ticker CCX. Obviously there is a little overlap between the two.
What I think these can do is offer protection against a dollar erosion which for many investors can be the solution. While I have used single currency ETFs for clients before it is important to understand this type of trade requires more in the way of analysis as some sort of change in the story in the Canadian dollar would obviously have a much larger impact on FXC than CCX. This is not to say that single currency ETFs are a bad idea but there is a different type of work load involved.