The current successor to a federal statute first enacted in 1917, and widely known as the “debt ceiling,” limits the face value of money that the United States may borrow. Congress has repeatedly raised the debt ceiling to authorize borrowing to fill the gap between revenue and spending, but in the summer of 2011, a political standoff nearly left the government unable to borrow funds to meet obligations that Congress had affirmed earlier that very year. Some commentators urged President Obama to ignore the debt ceiling and issue new bonds, in order to comply with Section 4 of the Fourteenth Amendment, which forbids “question[ing]” “[t]he validity of the public debt.” Others responded that such borrowing would violate the separation of powers and therefore that the President instead ought to refuse to spend funds that Congress had appropriated. In the end, eleventh-hour legislation averted the crisis, at least for the moment, but absent a substantial political realignment, there is reason to believe that a similar standoff could occur again [...]