Wow, 20 years is a long time. If inflation ramps up (e.g., temporary wage price spiral, QE, etc.), and the rate is increased to 8-10%, even temporarily, 20 year bonds will be selling at a loss, which means you could be stuck in them until maturity or until the market shifts. Keep in mind that, with sneaky tricks like QE, etc. the rates could go up in a similar time as the money supply is increasing (tho bonds will not be paying well during the QE).

Wow, 20 years is a long time. If inflation ramps up (e.g., temporary wage price spiral, QE, etc.), and the rate is increased to 8-10%, even temporarily, 20 year bonds will be selling at a loss, which means you could be stuck in them until maturity or until the market shifts. Keep in mind that, with sneaky tricks like QE, etc. the rates could go up at the same time as the money supply is increasing.