Even as a credit analyst, I agree that you can't really feel sorry for the bondholders here. If you want to lend in any market, you need to assume the risk that the debtor goes bankrupt. Pensioners are a different story though.
However it's absolutely not true that "a lot of money in the US is being lent with the assumption that creditors will always be bailed out by the state or federal government", at least not a large amount relative to the total bond market size. Rates are low now, yes, but that's because the Treasury rates are so low, not because of some implicit government backing of credit that is making assets less risky. In fact, spreads (bond yield - treasury yield) are near historical norms.
However it's absolutely not true that "a lot of money in the US is being lent with the assumption that creditors will always be bailed out by the state or federal government", at least not a large amount relative to the total bond market size. Rates are low now, yes, but that's because the Treasury rates are so low, not because of some implicit government backing of credit that is making assets less risky. In fact, spreads (bond yield - treasury yield) are near historical norms.