The Constitution grants only Congress — not the president — the power “to borrow money on the credit of the United States.” Nothing in the 14th Amendment or in any other constitutional provision suggests that the president may usurp legislative power to prevent a violation of the Constitution. Moreover, it is well established that the president’s power drops to what Justice Robert H. Jackson called its “lowest ebb” when exercised against the express will of Congress.
Worse, the argument that the president may do whatever is necessary to avoid default has no logical stopping point. In theory, Congress could pay debts not only by borrowing more money, but also by exercising its powers to impose taxes, to coin money or to sell federal property. If the president could usurp the congressional power to borrow, what would stop him from taking over all these other powers, as well?
So the arguments for ignoring the debt ceiling are unpersuasive. But even if they were persuasive, they would not resolve the crisis. Once the debt ceiling is breached, a legal cloud would hang over any newly issued bonds, because of the risk that the government might refuse to honor those debts as legitimate.