Interesting read, but there’s no reason to include “unfunded liabilities” in a calculation of the nation’s debt. Any one of those liabilities could vanish in an instant through a change in Federal law . . . and all them probably will, at some point in the future.
The legal challenges that would ensue will prevent these 'unfunded' liabilities for disappearing. Some may be reduced to a degree, but a lot of the contractual obligations will never go away.