Perhaps I'm a Constitutional hipster, in-so-far as I was talking about section 4 of the Fourteenth Amendment before it was cool to do so. After it had become cool, I felt moved to explain

[The Fourteenth Amendment] is indeed [the law that empowers the President to increase the ceiling] — where the only way not otherwise in violation of the Constitution to pay debt that has come due is to borrow beyond the existing limit. If the debt can be paid in some other way, then no special authority can be found for the President in section 4.

[…] The President doesn't get to say that he or she must raise the limit to continue funding institutions to which he or she can apply profound and moving terms, unless those institutions are indeed Constitutionally mandated.

With talk of the President raising the borrowing limit by decree again heating-up, I feel moved to labor aspects of what I'd earlier explained.

As debt comes due, for which sufficient funding has not been allocated, the Federal government can do one or more of five things:

• Default.
• Increase tax collections.
• Decrease other expenditures to allocate more revenue for debt service.
• Liquidate assets.
• Engage in new borrowing to service the debts from previous borrowing.

Advocates of the President raising the ceiling by decree want to pretend that the Constitutional prohibition of the first of these five options empowers the President to effect the last of these options by decree. But there would be three other options; it is appropriate to ask why the President wouldn't instead be required to choose one or more of the other three.

And, if a decision must be made amongst some or all of the four options not prohibitted by section 4 of the Fourteenth Amendment, it is not evident that it is the President's decision to make, even if the Congress will not. In the absence of Constitutional guidance, there is no apparent reason that abdicated legislative responsibility should go to the executive branch as opposed to the judicial branch.