A mistake: Mish wrote "the Pension Benefit Guarantee Corporation (PBGC). The PBGC is of course US taxpayers who should not have to pick up any of this tab at all (but they will)."
The fact: The PBGC is funded by premiums paid by companies. Taxpayers backstop that. Since PBGC is government run we can presume that they are incompetent in setting rates to match expenses, thus increasing taxpayer risk.