The rise of the major questions doctrine—the rule that says that in order to delegate to the executive branch the power to resolve a “question of ‘deep economic and political significance’ that is central to [a] statutory scheme,” Congress must do so expressly—threatens to unmake the modern executive’s authority over foreign affairs, especially in matters of national security and interstate conflict. In the twenty-first century, global conflicts increasingly involve economic warfare, rather than (or in addition to) the force of arms.

In the United States, the executive power to levy economic sanctions and engage in other forms of economic warfare are generally based on extremely broad delegations of authority from Congress. The major questions doctrine (MQD) threatens the ability to fight modern conflicts for two reasons. First, classic national- security-related conflicts—wars of territorial conquest, terrorism, or nuclear proliferation—increasingly are met with economic measures. But the statutes that authorize economic warfare actions are incredibly broad and recent administrations have interpreted these statutes in ways that risk running afoul of an expansive and free-form MQD. Second, “foreign affairs exceptionalism,” in which the Court decides not to apply the MQD to statutes involving foreign affairs, is not likely to work well as a response because what is “foreign” and “domestic” cannot be easily distinguished and attempts to do so will have perverse consequences.

The MQD raises serious problems for foreign affairs and national security. If the MQD is applied to domestic, but not foreign, delegations, then the executive branch will have an incentive to use broad foreign affairs delegations to accomplish domestic policy objectives in order to evade the safeguards and limits that attend domestic administrative action. At the same time, judges will have to police the porous boundary between “foreign” and “domestic,” with especially high error costs because wrong decisions will affect national security. If the MQD is applied to economic delegations that touch foreign commerce, the most likely consequence is that judges—particularly lower court judges—will be put in the position of second-guessing executive branch decisionmaking on precisely those questions—economic foreign policy questions of deep economic and political significance—on which the political branches enjoy both constitutional primacy and institutional expertise. This result is troubling; judges lack the knowledge and training to make effective decisions bearing on foreign policy, and putting them in the position to do so contravenes the norms of our legal system.