The problem with ETF’s is that they only protect against the declining dollar – you do not actually make any return.
For example, you buy fxe at $120. The dollar declines by 2%. Your investment in fxe is now worth $122.40 But gold, oil, and goods manufactured in Europe are now 2% more expensive. And in theory everything here at home also costs 2% more. With the “new” market basket used in calculating consumer price index, it is hard to see the increase, but it is there over time.
All the fund has done is preserve your wealth, not add to it. Right now FXE is up $.66 as the dollar has fallen another half cent or so. But in Europe, your hotel room just went up by the same amount.