We know interest rates are going to rise. They are being artificially manipulated right now in order to prop up the massive spending of the government. When they do rise, bond-holders will take it in the shorts. And it isn't as if there is a safer investment vehicle in real estate (currently in a false run) or stocks (which are also over-priced).

If I had any money to invest, it wouldn't be in stocks OR bonds, and not in real estate either. Any kind of fiat-based investment is nearly useless in the kind of inflation of I expect to hit the US economy with in the next 5 years.