[Editor’s note from Ryan Goodman: The legal backgrounder by Brian Egan and Tess Bridgeman on possible military actions against Iran included key questions about the role of the War Powers Resolution in assessing the legality of different policy options under U.S. domestic law. Their backgrounder recognizes the importance of historical practice in any such assessment, and one historical episode to which people have pointed involves the “Tanker War” and the US re-flagging of Kuwaiti vessels in the late 1980s. During this period, President Ronald Reagan agreed to the re-registration under American flags of vessels from Kuwait (which was exporting oil from during the seemingly-endless Iran-Iraq War) and he ordered U.S. naval forces to protect the vessels against Iranian attacks. There were significant concerns in Congress and the public about the dangers of the operations and the risk of the United States being dragged into broader hostilities.

I asked Todd Buchwald, who worked on war powers issues as a State Department lawyer during this period, to explain how the Reagan administration approached the war powers issues, and to offer observations about what conclusions, if any, might be drawn from those events. What he wrote follows.]


There are similarities between the two situations, but differences as well. I would mention three basic questions:

  1. Before one gets to the issue of restrictions under the War Powers Resolution (WPR), how did the Reagan administration assess its underlying authority to use force without authorization from Congress?
  2. Assuming the President had underlying authority to use force, what does the tanker war episode tell us about the treatment of the 60/90-day clock requirement under the WPR – will the clock start ticking?
  3. Assuming the WPR’s 60/90-day clock is triggered and then expires, would the President be legally compelled to terminate the use of force?


1. Threshold Question: Affirmative authority to use military force. On the first question, the Reagan administration did not view this as a close call. If President Trump eventually proceeds to order discrete strikes on Iran — along the lines of the strikes for which he withdrew authority this past week – the Executive Branch will doubtless argue that the attacks are similar to those ordered by President Reagan and can be conducted pursuant to the President’s authority under Article II, without need for congressional authorization.

True, it might well be argued that the surrounding circumstances are today very different than existed during the tanker war. Today’s Iran is far better equipped, not preoccupied with a life-and-death struggle against Iraq, and not degraded by eight years of war weariness — so that the risk of U.S. attacks against Iranian targets leading to a more protracted military engagement is much higher. But the two-pronged test that the Justice Department’s Office of Legal Counsel (OLC) has articulated is remarkably elastic and easily satisfied. It requires only that the President must have reasonably determined that

(1) the use of force would be in the national interest and

(2) the “anticipated hostilities would not rise to the level of a war in a constitutional sense.”

On its face, the first prong would only bar cases in which it could be shown that the President was unreasonable in concluding that a use of force was in the national interest. The debate about the reasonableness of any such determination is well worth having but is on its face political in nature. The second prong depends on “the anticipated nature, scope, and duration of the operations [being] sufficiently limited,” but “anticipated” is a funny word. Different actors will doubtless anticipate different outcomes, but the administration’s narrative will almost certainly include that the strikes being ordered will ultimately deter Iran and make a wider conflagration less likely. One can have grave questions about that narrative but administration lawyers will have little hesitation in pointing to a ready list of previous historical examples in which robust military engagement could have easily been anticipated (think Bosnia, Kosovo, Haiti, Libya . . . and even President Truman in Korea) to conclude that, based on historical practice, the President has sufficient threshold authority to order military action.

It is worth noting that the two-pronged test and the question whether the operations qualified as “war in a constitutional sense” were not — at least to the best of my recollection — a part of the debate during the tanker war and had not been embraced in OLC opinions on the WPR under Republican administrations, at least until it was featured in OLC’s May 2018 memorandum on US airstrikes against Syrian chemical weapons facilities. The idea of the second prong is derived from the “declare war” clause in the Constitution. In thinking about the issue, one approach is to focus on the meaning of “war” in this clause – hence an analysis of whether the contemplated operations reach the level of “war” in a constitutional sense. A second approach, however, focuses on the meaning to be attributed to the fact that the language is narrower than the original formulation, which would have given to Congress the broader power to “make” war.

The Reagan administration approach was reflected in Abe Sofaer’s testimony before the Senate Foreign Relations Committee in September 1988. Sofaer emphasized the inevitably fluid and political nature of the process, saying that “[t]he only way that the character and limits of such fundamental constitutional powers can be defined and understood is through the actions of the two branches in coping with real world events over the years.”

2. The Sixty-Day Clock. By the terms of the War Powers Resolution, the “sixty-day clock” (extendable to ninety-days if the President certifies an “unavoidable military necessity respecting the safety of United States Armed Forces”) begins to tick when US forces are introduced into “into hostilities or into situations where imminent involvement in hostilities is clearly indicated by the circumstances.” The basic underlying idea is that the President should not engage in ventures that will lead to protracted conflicts that the Congress and the American people will not sufficiently support. The risk that a venture ordered by the President (think the decision to reflag and protect the Kuwaiti vessels or the deployment of naval assets to do so) might lead to the eruption of a broader conflagration does not, however, necessarily mean that US forces are at this point being introduced into situations where imminent involvement in hostilities is clearly indicated by the circumstances.

During the tanker war, there were several particular military incidents that began at least as early as the Iraqi attack on the USS Stark in May 1987, and included incidents involving Iranian attacks between September 1987 and July 1988, that were easily characterized as involvement in actual hostilities, as opposed to imminent hostilities. Following some early incidents in which reports were not submitted to Congress, the Reagan administration fell into a familiar pattern of reporting incidents to Congress, saying it was doing so “consistent with the War Powers Resolution” but taking no formal position on whether it considered that US forces had been introduced into hostilities — actual or imminent. This position allowed it to maintain at least some nominal level of uncertainty about whether the 60-day clock had been triggered. The administration maintained that this approach “facilitated the President’s ability to proceed in a spirit of mutual cooperation with Congress and to ensure that Congress continues to be fully informed.”

But even on the premise that U.S. forces had been introduced into hostilities and that the clock had been triggered, the Reagan administration treated these incidents as discrete – as if each started its own 60-day period. This approach was reflected at various points in the letters that President Reagan submitted to the Congress – e.g, via language in the letters stating that US forces had “completed” their self-defense actions, or that we “consider the matter closed.” Under this construct, even if one considered that the incidents qualified as the introduction of forces into hostilities, the 60-day clock quickly reset to zero, and the question whether the administration was relying on constitutional arguments to continue operations could be avoided. There is of course a tension between treating each incident as a discrete episode for war powers purposes and treating them later, for purposes of defending the United States in the Oil Platforms case before the International Court of Justice, as part of an integrated whole (so that the proportionality of the measures taken in self-defense against Iran need not be measured against the immediately preceding attack, but rather against the overall threat being addressed). Nevertheless, in the event of a series of attacks that could be described as discrete, it is likely that the Trump Administration would look to utilize this same type of approach.

3. The WPR’s Mandatory Withdrawal Provisions. Sofaer’s testimony on this point stated the Reagan administration’s views clearly: “We believe that this 60-day provision is unconstitutional.”

* * * *

The discussion above focuses primarily on the Reagan administration’s approach, recognizing full well that there are many in the Congress and the public that did not agree with it then and would not agree with it now. Why focus so heavily on the Executive Branch view of these questions? It is not that its view is “correct,” or even that it is more reasonable than contrary views. In practice, however, it is the President that makes the decision whether to use force, the President that applies these tests, and the President that ends up being the judge of the reasonableness of his own conclusions. Indeed, it has been acerbically observed that “any President faced with the winding down of the 60-day clock would identify some justification for avoiding [its] terms. … No responsible chief executive would terminate a military operation deemed in the national interest in the face of congressional inaction.”

For their part, the courts have been persistently resistant to invitations to adjudicate the competing views of the proper congressional and executive roles. In the case of the tanker war, for example, the D.C. District Court had little trouble dismissing a suit submitted by Representative Michael Lowry and 110 other members of Congress that sought a declaration that would trigger the 60-day clock. This may or may not be the way things should be, but it means that — if the President is to be dissuaded from acting – pure legal arguments will be insufficient.

The tanker war episode was an important catalyst for consideration of serious but still-unfinished efforts to reform the war powers legislation, including notably legislation introduced by Senators Mitchell, Nunn, Byrd and Warner that aimed to establish a better consultative process regarding use of force decisions but eliminate the 60/90-day withdrawal provisions. Putting aside questions about whether the Reagan administration in fact consulted adequately (and there was significant criticism that the Executive Branch had in fact under-consulted), Sofaer set out a foundational point:

“No Executive policy or activity in this area can have any hope of success in the long term unless Congress and the American people concur in it and are willing to support its execution.”

The War Powers Resolution can serve as a lever for galvanizing political forces; at the end of the day, however, it is only through public pressure, active congressional opposition, persuasion from influential voices, or even new legislation that the President will be dissuaded from taking military actions that he has otherwise concluded are needed. The Congress possesses immense power – both legal and political – to re-steer the course of events, but the existence of the WPR is not by itself sufficient to make that power effective.


[Editor’s note: Readers may also be interested in Mark Nevitt’s The Missing Piece in US-Iran Drone Dispute: Navigational Freedoms and the Strait of Hormuz, and Mike Schmitt’s Top Expert Backgrounder: Aborted U.S. Strike, Cyber Operation Against Iran and International Law]

Photo: A US Navy escorts the 12th US reflagged Kuwaiti tanker convoy 22 October 1987 Norbert Schiller/AFP/Getty Images