"put it all on black!"

yeah. That might work out, but my investments are diversified more. I have real estate in the form of my house. I have stocks and bonds in my 401k. I have government in my social security. They are completely separate, so if any one fails I'm still okay. (well if the government fails I'm probably in trouble no matter what, but social security is limited at best)

Is this US real estate, US stocks, US bonds, and US social security? :-)

I've tried to diversify to more international mutual funds, but they also tend to have higher fees.

My 401k does have some international funds. While it is good to have a bit, they are as you say higher fees and so not always a good investment.

I'm not sure they are really diversification though. The major US companies have a lot of international exposure already so you don't gain much diversification. And of course they don't really protect you from a collapse of the US government (odds are either they are hit as well, or you can't prove you own them anymore)