I don't see it as being as unfair as holding people to an agreement formed 3/4 of a century before by people long-dead who thought that they were forming a voluntary union (small "u") and had no way of foreseeing the problems that would arise in the future.
The fly in the buttermilk is that the debt was extant in 1861. The feds had assumed the debts of Texas. the feds had paid hundreds of millions of dollars to move the indians out of Georgia and Florida.
It is right to just let those states walk on money spent on their behalf in living memory?
Which state picks up the tab? The one with the latest postmark on its secession documents?
It's nuts. It's absurd and unjust, just as President Lincoln said.
Walt
Needless to say, you haven't convinced me. I can certainly agree that an equitable handling of the debt is a problem, but not an insurmountable one as you wish to conclude. And I think it is nuts to say that the people can be held hostage to the existence of common debt. It certainly would be a good reason to limit federal functions to the utmost (say like to those mandated by the Constitution) to absolutely minimize federal debt.