The validity of the public debt of the U.S.....shall not be questioned (14th Amendment)

[Yo_Mama]

16. Congress hasn't passed a budget in years

Instead they go through continuing spending authorizations.

But you are confusing spending and debt. Congress has the power to raise revenue, authorize spending, and the power to raise money by borrowing. Only Congress has the power to raise money by borrowing. Section 8.
http://www.law.cornell.edu/constitution/articlei#section8

The Executive does not, and if the Executive were to do so without Congressional authorization, the debt would not be legal public debt subject to the 14th amendment.

Once Congress has authorized an expenditure, the authorized department of the Executive has that ability to spend that money - if we've got it. The authority to spend that amount of money does not extend to the ability to go out and borrow that money.

There is an ample body of caselaw long in existence that would govern the ajudication of such a legal question, should it ever occur. All corporations (non-natural persons) have designated officers with various powers which are granted to them by resolution. Take for example a Director of an Association. The association executes a resolution saying that this Director has the ability to spend up to such an amount. If, however, the Director wants to spend the money but the Association doesn't have it, that doesn't give the Director the authority to go out and borrow that amount of money - under contract law, the power to spend is not the power to borrow. The Director only has the legal authority to borrow if that power has been explicitly granted, and believe me, this question has come up before, and been settled before, and always to the detriment of the creditor which extended the unauthorized credit.

What happens in such a case is that the corporation (non-natural person) is NOT liable for the debt. The creditor may seek to recover from the person who actually borrowed the money without authorization, but of course this would not help any creditor of the Treasury because the Treasury has no assets in its own right.

This is not legal rocket science. It's kind of basic, really.