The Purpose Of The Fourteenth

The purpose of the fourteenth amendment was to prevent the South from trying to, in effect, prolong the Civil War and to extract financial revenge upon the North for winning it. It assured that the South could not disenfranchise the freed slaves, it prevented those who participated in the rebellion from holding any future government office, and it precluded the South from trying to recoup any of its costs for fighting the war.

To try to use that now to circumvent the will of Congress is absurd, even when the will of Congress is sheer jackassery. Congress is still Congress.

The paragraph in the amendment regarding debt reads in its entirety,

The validity of the public debt of the United States, authorized by law, including debts incurred for payment of pensions and bounties for services in suppressing insurrection or rebellion, shall not be questioned. But neither the United States nor any State shall assume or pay any debt or obligation incurred in aid of insurrection or rebellion against the United States, or any claim for the loss or emancipation of any slave; but all such debts, obligations and claims shall be held illegal and void.

The declarative part of the amendment is the wording which states that all of the debt incurred by the South in the course of rebelling against the nation is null and void, and the opening statement is merely a preface explaining the the following statement is not to be taken to invalidate any legitimate national debt; to assure that the amendment invalidates debts of the South for the war, but not of the North.

You don't base government principle on what amounts to a "whereas" clause in an amendment.