Congress is currently revisiting the authorizations for use of military force (AUMFs) it enacted in 2001 and 2002, which presidents from George W. Bush to Donald Trump used to claim congressional support for military actions in Afghanistan, Iraq, Libya, Somalia, Syria and Yemen. Such expansive use of the AUMFs is far removed from Congress’s original aim: to neutralize the terrorist organizations and governments responsible for the Sept. 11 attacks and counter the perceived threat posed by Iraq (2002). Repealing the AUMFs is a laudable effort and one that should be encouraged; for too long, Congress has ceded to the president significant national security decision-making authority involving the use of the military force without providing a meaningful check on that authority.
Still, repealing these authorizations alone is unlikely to provide a meaningful congressional check, because President Biden and his successors may assert authority to pursue military actions without congressional authorization under Article II of the Constitution. Members of Congress are right to worry, for example, that Biden could retaliate against Iran-backed militias and claim the legal authority to do so under Article II.
To be sure, Article II has been understood to give the chief executive the authority to defend the nation. Since the Prize Cases, decided in 1863, the Supreme Court has held that the president has the implicit power to engage in self-defense without prior congressional authorization. The case concerned President Abraham Lincoln’s blockades of ports to prevent the Confederacy from gaining access to supplies and war material, and the court essentially said that the president, in either the circumstance of a foreign invasion or civil war, need not wait for Congress before acting.
Of course, the president should have the power to act in self-defense, and the courts should defer to the president’s determination that such action is warranted. The problem is that no court can anticipate all of the circumstances that could implicate the defense of the nation — such as when the president argues that attacks against United States proxies or other national interests are covered by Article II’s implicit self-defense authority.
In recent cases challenging Bush’s authority to take certain actions in response to Sept. 11, the Supreme Court carefully avoided weighing in on whether those actions were justified under the Constitution. It is likely that the courts will continue to avoid deciding the vexing and largely political questions involving the limits of the president’s Article II authority.
This brings the matter back to Congress. Unlike the courts, the legislative branch is not without significant constitutional power when it comes to national security decision-making involving the use of military force. In addition to the authority to declare war and to authorize military actions, the Constitution assigns Congress the responsibility to raise and support the armed forces. Nothing in the Constitution prevents Congress from imposing some reasonable limits on the president’s self-defense authority so that this and future presidents cannot take broad military actions simply by claiming self-defense under Article II.
In the famous Steel Seizure case, one justice suggested a way in which Congress might be able to articulate a workable check on expansive claims of presidential authority. That case involved the seizure of domestic steel mills on President Harry S. Truman’s order, ostensibly to prevent any interruption in steel production due to labor strife from undermining the U.S. effort in Korea. A majority of the Supreme Court concluded that the president had no authority under the Constitution to issue such an order.
Concurring in the result, Justice Tom Clark noted that, while the “limits of presidential power are obscure,” when “Congress has laid down specific procedures to deal with the type of crisis confronting the President, he must follow those procedures in meeting the crisis.” Further, Clark concluded that, whether the president can act in the absence of congressional action depends “upon the gravity of the situation confronting the nation.”
Beyond merely repealing the 2001 and 2002 AUMFs, Congress should pass legislation that draws a line distinguishing between, on the one hand, threats to the nation from invasions and insurrections; and, on the other, threats that may harm American interests but that are found far from our shores. There will be a gray zone in the middle, but at least in the face of such congressional action, the president could not simply regard the self-defense authority under Article II as a blank check for virtually any military action.
Lawrence Friedman is a professor of privacy and constitutional law at New England Law in Boston. Victor Hansen is a professor of criminal justice and national security law at New England Law in Boston. They are the authors of “The Case for Congress: Separation of Powers and the War on Terror.”