Two interrelated fears that have caused mounting public alarm with respect to the Trump Administration involve unchecked executive power and the erosion of the rule of law. These worries have intensified in debates about the legality of President Trump’s decision to bomb Iranian nuclear facilities more than a week into Israel’s war against Iran. Members of both houses of Congress had introduced resolutions to try to prevent Trump from taking such military action without its authorization. But the energy that some lawmakers had mustered for a rare attempt to assert Congress’s constitutional power against Trump seemed to dissipate, at least while they expected a ceasefire between Israel and Iran to hold.
One would normally look to Supreme Court precedents to determine the constitutionality of a Presidential action. But no cases provide legal answers about the permissibility of attacks like the one on Iran. The only relevant case from the Court dates to the Civil War. It states that Congress has the sole power to “declare war,” but that, in the event that a foreign nation invades the U.S., congressional authorization is unnecessary and the President’s constitutional power as the Commander-in-Chief is sufficient to take action. The Court noted that the President cannot “initiate the war,” but it has never provided an authoritative definition of “war,” as opposed to armed conflict.
Congress has not formally declared war since the Second World War, but it has sometimes authorized Presidents to use military force in conflicts colloquially known as wars—for example, in Vietnam, the Persian Gulf, Afghanistan, and Iraq. But, when Congress has given no such authorization, Presidents have often turned to the Justice Department’s Office of Legal Counsel. O.L.C. issues opinions that are not binding law, but which attempt to present legally correct boundaries that the President should respect. Presidents have regularly acted unilaterally to enter significant hostilities on the basis of those opinions, including in the Korean War, in Kosovo, and in Libya.
Congress, in the War Powers Resolution of 1973 (enacted over the veto of President Nixon, who thought it unconstitutional), aimed to check the unilateral Presidential use of force, requiring, among other things, that the President consult Congress before sending armed forces into hostilities and obtain congressional approval to deploy troops in conflicts for more than sixty days. But both Democratic and Republican Presidents have not fully complied, and Congress hasn’t done much about it. In recent weeks, some lawmakers proposed new War Powers Resolutions to prevent Trump from attacking Iran again unless Congress authorizes it, but the House Speaker, Mike Johnson, resisted the idea and declared that the existing War Powers Resolution was an unconstitutional infringement of the President’s power as Commander-in-Chief.
During the past several decades, O.L.C. has produced opinion after opinion that has been staggeringly expansive with respect to that power. Each armed conflict that a President undertook without congressional authorization became a precedent that further enlarged what the executive branch considered constitutionally permissible. That is how we got to a situation in which a President can reasonably claim that it is lawful, without congressional approval or even consultation, to drop bunker-busting bombs on a country that has not attacked the U.S. One might assume that Trump wouldn’t care a whit about precedent, but the telltale way he described the operation in a letter to Congress days after the strikes suggested that he was closely informed by past executive practice. He alluded to key formulations from previous O.L.C. opinions, stating that his strikes “discretely targeted” Iran’s nuclear facilities, were “limited in scope and purpose,” and did not involve ground forces—meaning that the operation fit the criteria of what O.L.C. has said falls short of war, such that congressional authorization was unnecessary.
Trump’s justifications also reflected O.L.C. precedents maintaining that a President can unilaterally use military force abroad to pursue “national interests” and “collective self-defense.” The office has construed “national interests” very broadly, to include “ensuring the safe delivery of food and medicine in Somalia,” under the first President Bush; “assisting an ally or strategic partner,” Iraq, under President Obama; and deterring “the use and proliferation of chemical weapons,” in Syria, during Trump’s first term. And “collective self-defense” can mean not only repelling an imminent attack but also warding off future attacks and defending allies.
Jack Goldsmith, a foremost expert on war powers and a professor at Harvard Law School, wrote, in October, 2023, that, under the body of O.L.C. opinions, “just about any conceivable circumstance” in which a President “would think it prudent to use force in the Middle East” can be justified. Slowing down Iran’s ability to create nuclear weapons would satisfy the “national interests” test as well as the “collective self-defense of our ally, Israel,” as Trump put it. More recently, Goldsmith rued the troubling reality that “there is no constitutional rule that would answer the question” of whether the Iran strikes were unlawful. But some lawmakers may believe that it is time for Congress to rethink the acceptance of past executive-branch practice as a justification for future unilateral military actions. Not least because a leaked preliminary Defense Intelligence Agency report suggesting, to Trump’s ire, that his attack had not “completely and totally obliterated” Iran’s nuclear capabilities, if proved correct, may lead him to feel that it is in the “national interest” to try again. (The Administration said that it might now limit the intelligence it shares with Congress.)
The courts largely stay out of war-powers debates because those debates are often deemed to entail policy questions rather than legal ones. So if Congress persists in not checking the President’s use of the military, or even believes that such checks are unconstitutional, his unilateral power will remain nearly unlimited. Before the Iran strikes, concerns about Trump and the military were focussed on his federalization of the California National Guard, which the Administration justified on the theory that violent incidents among those protesting ICE in Los Angeles had turned into a “rebellion” against the U.S. The Ninth Circuit found that Trump’s actions were likely consistent with a statute stipulating that the President may take such steps when “unable with the regular forces to execute the laws of the United States.”
We are learning that, at home and abroad, the ability to curb the most dangerously consequential uses of Presidential power relies mostly on the self-restraint of the Commander-in-Chief. Law gets us only so far, or, sometimes, nowhere. ♦
