Of Course It’s a War

The United States and Iran are at war. They have been at war for at least 89 days, since Feb. 28. And U.S. President Donald Trump’s prosecution of this war of choice without authorization by Congress is unconstitutional.

Those simple propositions are—and should be—obvious. The United States has 50,000 service members deployed to the region and it has employed an astounding collection of military hardware, including three carrier strike groups, two of which remain on station there. By April 8, it had launched 10,000 sorties against at least 13,000 Iranian targets; damaged or destroyed more than 150 Iranian warships, as well as every one of Iran’s submarines; and killed (in combination with Israel and other belligerents) some 3,500 Iranians. Since April 13, the United States has enforced a blockade against Iranian ports, interdicting at least four and turning around at least 100 ships. By May 12, the U.S. operation had cost at least $29 billion and resulted in the loss or damage of at least 42 U.S. combat aircraft.

The United States and Iran are at war. They have been at war for at least 89 days, since Feb. 28. And U.S. President Donald Trump’s prosecution of this war of choice without authorization by Congress is unconstitutional.

Those simple propositions are—and should be—obvious. The United States has 50,000 service members deployed to the region and it has employed an astounding collection of military hardware, including three carrier strike groups, two of which remain on station there. By April 8, it had launched 10,000 sorties against at least 13,000 Iranian targets; damaged or destroyed more than 150 Iranian warships, as well as every one of Iran’s submarines; and killed (in combination with Israel and other belligerents) some 3,500 Iranians. Since April 13, the United States has enforced a blockade against Iranian ports, interdicting at least four and turning around at least 100 ships. By May 12, the U.S. operation had cost at least $29 billion and resulted in the loss or damage of at least 42 U.S. combat aircraft.

Iran, for its part, has launched thousands of missiles and drones at U.S. bases in the region, inflicting substantial damage to U.S. military infrastructure; killed at least seven and wounded at least 409 U.S. service members; and destroyed as much as 20 percent of the U.S. fleet of MQ-9 Reaper drones. It declared the Strait of Hormuz closed to hostile shipping, causing a global oil shock, and attacked U.S. warships in an effort to enforce that declaration. This accumulation of facts amounts to war in every meaningful sense. Certainly it is, as philosopher Emmerich de Vattel defined the term, a “state in which [nations are] prosecut[ing] [their] right by force.”

But acknowledging the existence of a war between the United States and Iran is a substantial legal problem for Trump. The Constitution assigns to Congress alone the power to choose whether or when the United States goes to war. Although it has long been accepted that the president may use force in self-defense, in response to an attack on the United States, he simply lacks the legal authority to initiate a war of choice without Congress’s express endorsement. So, since the inception of Operation Epic Fury, the president and his coterie of senior political appointees have engaged in a dissembling and sometimes bumbling campaign to recast this war as anything but. Most recently, the Trump administration’s nominee to be the legal advisor of the State Department refused even to acknowledge that the United States imposed a blockade on Iran.

Regardless, the weight of law and history shows unquestionably that Operation Epic Fury is a war. Take the United States’ imposition of a blockade on Iran since April 13. The Supreme Court has repeatedly acknowledged that a blockade is a tool of warfare—a belligerent right—that is available to U.S. or other armed forces only during a war. Indeed, according to Justice Robert Grier, writing for the Supreme Court in the Prize Cases during the Civil War, “The proclamation of blockade is itself official and conclusive evidence … that a state of war existed.” In 1878, Justice Nathan Clifford, concurring in Ford v. Surget, remarked that “[l]awful blockade can only be established by a belligerent party … [because] the interruption of the untrammelled right [for neutral countries to trade with all other countries in time of peace] can only be justified because the party imposing the conditions and restrictions is invested with belligerent rights under the law of nations.” Likewise, more than 60 years earlier, Justice Joseph Story wrote in 1814 in McCall v. Marine Insurance Company, “The right to blockade an enemy’s port with a competent force is a right secured to every belligerent by the law of nations.”

Beyond the Supreme Court, the current Department of Defense Law of War Manual characterizes blockades as “operation[s] by … belligerent State[s]” and even the Department of Justice’s Office of Legal Counsel (OLC) explained in 1962 that a blockade is an “incident to a state of war.” It is, at bottom, impossible for the United States to impose and enforce a blockade against a foreign country without a war, as the term is used in the U.S. Constitution.

Nevertheless, the Trump administration’s counterargument rests on a decades-long accretion of OLC opinions that have purported to define “war in the constitutional sense”—military activity that would require Congress’s advance approval—in an arbitrarily narrow manner. There has long been good reason to view these “promiscuously generous executive branch legal opinions” with skepticism, but the current U.S.-Iran war highlights their defects. According to OLC, war in the constitutional sense requires a military operation that crosses some fact-specific and ill-defined threshold based on its anticipated nature, scope, duration, and risk that the United States “would encounter significant armed resistance or suffer or inflict substantial casualties.”

Over the last 30 or so years, OLC has produced memos determining that the “consensual” deployment of U.S. forces to Haiti in 1994, deployment of U.S. forces to Bosnia in 1995, and the 2011 bombing campaign in Libya, among others, were not war in the constitutional sense. In generating these opinions, OLC’s iterative reliance on its earlier analyses has worked as a one-way ratchet and more or less flattened its test for “war” to a single threshold question: Does the president intend to introduce more than 20,000 U.S. ground forces into hostilities? Thus, with respect to the January 2026 capture operation of former Venezuelan President Nicolás Maduro, OLC remarked:

Although not dispositive, we have consistently treated the need to involve American ground forces as fundamentally different in kind than airstrikes, whether by manned aircraft or drones, due to the risk of immediate of casualties; the risk of escalation; and the difficulties of immediate extraction once American soldiers are under fire within hostile territory.

But even in that operation—which in fact involved the hostile insertion of U.S. ground forces into Venezuela, U.S. casualties, and Maduro’s ouster—OLC assessed that the size of the invading U.S. force was “within the range of activities that we have found to be within the President’s unilateral constitutional authority” because they involved considerably fewer “than the 20,000 troops we approved to assist in the removal of the Haitian dictator in the early 1990s under roughly analogous circumstances.”

So, under OLC’s approach, the president’s intent to deploy fewer than 20,000 ground forces almost certainly means an operation does not amount to war; and his intent to deploy more than 20,000 ground troops may rise to the level of war if the operation is expected to be “prolonged” with “substantial military engagements, typically involving exposure of U.S. military personnel to significant risk over a substantial period.”

Insisting, as OLC does, that a substantial deployment of U.S. ground forces is necessary to require congressional approval of military force is both ahistorical and pernicious. On the one hand, it disregards early U.S. practice even while insisting that executive branch practice has glossed the bare text of the Constitution. For example, Presidents John Adams and Thomas Jefferson each sought congressional approval before using the U.S. Armed Forces to prosecute the Quasi-War and the First Barbary War, respectively. The Quasi-War was almost entirely a naval endeavor; and the First Barbary War featured limited land warfare, including an incursion of just eight U.S. Marines and 500 foreign mercenaries. Despite having received congressional approval—and notwithstanding Jefferson’s insistence that congressional approval was necessary for anything beyond purely defensive force during the First Barbary War—these small-scale wars would not require such approval if OLC’s threshold focus on the substantial deployment of U.S. ground forces were correct.

This insistence also appears inconsistent with at least some more recent practice. For example, the George W. Bush administration sought and received congressional authorization for its war to topple the Taliban and evict al Qaeda from Afghanistan. Although expected to be of uncertain duration, initially, that campaign envisioned heavy reliance on airstrikes and standoff weapons, augmented by special operations forces not to exceed the “smallest possible U.S. military presence on the ground”; direct action targeting al Qaeda and Taliban leaders; and reliance on local proxy forces. In contrast to Operation Epic Fury, the congressionally authorized Operation Enduring Freedom’s opening salvo involved just 40 to 60 U.S. aircraft and 50 cruise missiles, striking 31 targets. During the 76-day campaign culminating in the collapse of the Taliban, the United States deployed approximately 2,000 U.S. forces to Afghanistan and flew just 6,500 sorties.

The comparable scales of Operation Epic Fury and Operation Enduring Freedom, the latter’s use of ground elements substantially lower than OLC’s threshold, and its congressional authorization at least suggest some U.S. practice that rejects OLC’s approach. Of course, the U.S. war in Afghanistan ultimately dragged on for 20 years—but the failed 19-year-plus project to quash the Taliban’s post-collapse insurgency and prevent its return was hardly anticipated when the need for authorization was assessed. Wars are unpredictable and potentially extremely costly in terms of blood, treasure, and global standing—which is why the Constitution assigns their initiating to Congress, not the president.

On the other hand, as the United States has increasingly relied on air power, proxy or partner forces to provide ground elements, and remote warfare—often in combination—OLC’s approach has aggrandized and liberalized the president’s ability to use military force abroad without congressional authorization due to changes in technology and doctrine rather than law. Indeed, Trump was reportedly briefed by the chairman of the Joint Chiefs of Staff in the days leading up to the launch of Operation Epic Fury that “a military campaign against Iran could carry significant risks, in particular the possibility of becoming entangled in a prolonged conflict,” and the probability that Iran would close the Strait of Hormuz and strike U.S. bases in the region in response was patent.

These risks would seem to rise to the level of OLC’s war-in-the-constitutional-sense but for the absence of an anticipated deployment of U.S. ground forces. Consequently, the realm of popular accountability for warfare has shrunk and narrowed, while the domain of unilateral presidential action has vastly expanded. That trend is likely to continue or even accelerate, as war is increasingly prosecuted by remotely controlled or even autonomous robots. Finally, as Operation Epic Fury has starkly demonstrated, OLC’s threshold focus on the size of a possible ground deployment simply ignores naval warfare—a bizarre blind spot given the historical and geographic context in which the Constitution was drafted.

Altogether, Operation Epic Fury demonstrates (again) the rotten practical state of war powers in the United States. Through the decades-long efforts of the executive branch and the derelict acquiescence of the legislative branch, the United States has arrived exactly at the place the founders sought to avoid: One man now unilaterally commits the country to large-scale military adventurism, resulting in substantial material destruction, U.S. casualties, and a global economic shock. Congress must reassert its constitutional role in war powers. Disapproving the current war on Iran, rejecting OLC’s unconstitutional interpretation of war in the constitutional sense, and insisting that the president withdraw U.S. forces from this war is a good place to start.