The only thing we can be sure of is that this bull market will eventually end. You can protect yourself in several ways. Then, as stocks continue to rise you will be forced to move money from stocks to cash as stocks rise. The same rising interest rates will cause bond prices to decline. You can also be fairly certain that a declining American market will be contagious, bringing down other markets.
Cash is the answer.
We're not like the people with hundreds of thousands in funds you usually seem to write about, but I bet lots of others are in our boat. I need some ammunition to convince my husband that contributing to his 401-k now is essential. I'm the money manager in the family. I think we should at least double that, but he claims we can't afford it. Otherwise, in 20 years we'll be in far worse shape.