In June, the Senate joined the House in voting for a concurrent resolution under the 1973 War Powers Resolution directing President Donald Trump to remove U.S. armed forces from hostilities against Iran. The passage of House Concurrent Resolution 86 (H. Con. Res. 86) by both chambers marked the first time that the legislature had successfully used this mechanism designed to halt unauthorized use of military force by the president.
Notwithstanding this historic directive by Congress, Trump refused to remove U.S. forces from hostilities. Instead, he has announced a fragile ceasefire to be “over,” reinstated a naval blockade, and resumed bombing Iran—continuing a war that one of us previously characterized as already “triply illegal.” This unnecessary conflict has been a massive strategic blunder with tragic human consequences. Trump’s Iran war has thrown the region into disarray, perhaps eroding irrevocably freedom of navigation through the Strait of Hormuz (possibly setting a pernicious precedent for other straits), causing disastrous economic ripple effects, and necessitating a deferral of nuclear negotiations in favor of prioritizing ending the conflict Trump began.
In ramping up hostilities without congressional authorization, the Trump administration seems to be relying on a theory that recent U.S. strikes constitute distinct “hostilities” from the bombing that began in February and thus are not subject to the same 60-day clock under the War Powers Resolution that requires termination of hostilities unless authorized by Congress. In short, the administration is suggesting this is a new war. This attempted end-run around the statute’s requirements constitute what one of us has termed the “salami-slicing” approach – an interpretation previously relied on by administrations of both parties.
Trump’s defiance of the people’s representatives compounds his disregard for the constitutional and statutory constraints on the use of force and underscores the need for Congress to take firmer action—both to end the current war with Iran and prevent any U.S. president from launching the United States into a similar conflict in the future. Among other tools explained in this article, Congress needs to deploy the ultimate war power—the power of the purse—both to prohibit funding for any further hostilities with Iran and in structural reform legislation to bar funding for any other unauthorized, offensive hostilities.
Why H. Con. Res. 86 Makes Plain the President Is Acting at the “Lowest Ebb” of His Authority
Passage of H. Con. Res. 86 was possible because of procedures Congress codified in the War Powers Resolution allowing it to terminate unauthorized presidential uses of force, but those procedures are just one part of a statutory framework intended to police the slippery slopes that can lead to war. Enacted in 1973 over President Richard Nixon’s veto, and in the context of an unauthorized bombing campaign in Cambodia (Operation Freedom Deal), the War Powers Resolution sought to restore the constitutional balance with respect to the use of military force by constraining unilateral military action by the president and forcing transparency. Consistent with an understanding of the Constitution in which the president’s unilateral authority to use military force was limited to repelling sudden attacks, Congress specified in the War Powers Resolution that in the absence of congressional authorization, the president may only unilaterally introduce U.S. armed forces into hostilities in response to a “national emergency created by attack upon the United States, its territories or possessions, or its armed forces.”
One means of restricting presidential unilateralism was a mechanism in the War Powers Resolution to allow members in either chamber to force a vote on a concurrent resolution requiring the president to remove U.S. armed forces from hostilities that had not been authorized by Congress. As a concurrent resolution, such a measure would not be presented to the president for his signature or veto – that is, it did not follow the procedures in the Presentment Clause of the Constitution.
Even prior to the enactment of the War Powers Resolution, there was debate in Congress on whether such a concurrent resolution would have the binding effect of law. Once the War Powers Resolution became law, the executive branch consistently objected to the provision as unconstitutional.
In 1983, the Supreme Court – in a separate context – held that legislative vetoes were unconstitutional. The case, INS v. Chadha, is widely viewed as casting the WPR’s concurrent resolution mechanism into further constitutional doubt. In response to Chadha, Congress amended the War Powers Resolution to provide for expedited procedures in the Senate (but not the House) for voting on a joint resolution—which would be presented to the president for signature, and is in turn also subject to presidential veto. As Professor Michael Glennon has argued, the Court could limit Chadha to its facts, or at least distinguish contexts like the War Powers Resolution in which Congress is exercising its own express constitutional authority (as one concurrence in Chadha would have done). But the Court seems unlikely to do so in the near term.
Regardless of the status of the concurrent resolution after Chadha, H. Con. Res. 86 is a legally significant development. Having been approved by both houses, Congress as a body has now clearly expressed its opposition to Trump’s war with Iran and directed its termination. Trump—acting in defiance of this clear congressional directive, is thus at his “lowest ebb” in Justice Robert Jackson’s scheme of executive power in his Youngstown Sheet and Tube Co. v. Sawyer concurrence.
To explain, in that opinion, which has become the dominant framework the judiciary uses in disputes regarding claimed executive authority, Jackson defined three categories of presidential power:
- First, when the president is acting “pursuant to an express or implied authorization from Congress,” which makes presidential authority the strongest “for it includes all that he possesses in his own right plus all that Congress can delegate;”
- Second, the zone in which Congress has neither granted or denied authority and the president “can only rely upon his own independent powers;”
- Third, when “the President takes measures incompatible with the expressed or implied will of Congress.” It is this third category in which presidential power “is at its lowest ebb,” because the president is relying on only his own constitutional authority “minus any constitutional powers of Congress over the matter” (emphasis added).
The text of the War Powers Resolution itself should make plain that the president is already acting in a way that is “incompatible with the expressed or implied will of Congress” with his war in Iran. If there were any doubt, H. Con. Res. 86 removes it: by continuing the Iran war, the president is acting against the express “will of Congress.”
In the Youngstown framework, we must then subtract Congress’s substantial constitutional authority over war powers from any authority the president has independently. In the context of the Iran war, which is not even in legitimate self-defense let alone necessary to repel a sudden attack, it is clear that the president simply does not have independent authority in Article II on which to act (that is, whatever concurrent or even unilateral authority he may have to repel sudden attacks, or perhaps rescue U.S. nationals in peril or the like, it is not implicated here). From that baseline, Congress’s considerable war powers, specifically enumerated in Article I, must be subtracted, putting Trump’s executive authority in this case in the realm of negative numbers.
In sum, Trump, acting at his “lowest ebb,” is waging his war on Iran not only in violation of the Constitution and the United Nations Charter, but against the express will of the people’s elected representatives in violation of the War Powers Resolution itself (the 60-day termination clock having long since run out) and H. Con. Res. 86.
Reasserting Congress’s Constitutional Prerogatives
Although the vote on H. Con. Res. 86 was both historically and legally significant, it did not stop Trump from continuing his unauthorized war with Iran. To practically constrain his military adventurism, Congress will need to resort to other tools—in particular the power of the purse.
Immediate Action: A Funding Prohibition
Senators opposed to Trump’s war on Iran succeeded in blocking a floor vote on the National Defense Authorization Act. This congressional show of resolve is a laudable step to reinforce the message sent by the recent concurrent war powers resolution. There are other actions Congress should take as well.
In the near term, Congress should also include a funding prohibition on further unauthorized hostilities with Iran in any available legislation, including the supplemental appropriation the Trump administration requested in connection with the Iran War.
The enactment of similar funding prohibitions beginning in 1973 were the mechanism by which Congress ultimately forced the Nixon administration to end its bombing campaign in Cambodia. With respect to a funding prohibition, it is noteworthy that the chair of the Senate Appropriations Committee, Susan Collins (R-ME), is up for re-election and may find herself under increased pressure to further oppose the president’s unpopular war.
Ongoing Action: Oversight, Transparency, and Public Attention
Congress should also use all of the tools at its disposal to ensure the American people understand the costs of this war, to force transparency, and to hold administration officials accountable for the war and its consequences. This crucial oversight and legislative work should be done in a bipartisan manner whenever possible – the fundamental issue is vindicating Art. I prerogatives and reining in an errant executive engaging in unauthorized war. These are priorities that ought to be advanced by members of both political parties regardless of who is in the Oval Office. The vote on H. Con. Res. 86, and the upcoming midterm elections, could make at least some further bipartisan action possible.
That said, members of Congress should act in as broad-based and coordinated a manner as possible even if they are only able to use the tools available to the minority. Members can, for example, so long as the unauthorized war continues: object to unanimous consent for legislation, resolutions, and nominees; place holds on bills and nominees; use the filibuster on the Senate floor; move to adjourn hearings; and invoke the “two-hour rule.”
Members can also make requests for information from administration officials and agencies. Even if those go unanswered, they create a useful record of the information the Congress and the public will eventually need to ensure accountability. Shadow hearings can also be useful toward these ends, even if they are not as well publicized as formal committee hearings would be.
Of course, all of these actions are far more effective if they are coordinated and consistently tied to the demand that unauthorized hostilities be ended.
In addition, members in both chambers can use the microphones that come with holding elected office to continue making the war’s costs apparent to the American people. They can host town halls with their constituents, hold press conferences, and work with civil society groups in their jurisdictions and beyond to amplify a steady drumbeat of voices in opposition to unauthorized war.
Future Action: Laying the Groundwork for Structural War Powers Reform
More fundamentally, Trump’s disastrous war on Iran underscores the need for structural reform to prevent this or any future president from unilaterally embarking on a similar military misadventure. Structural reform will entail an overhaul of the 1973 War Powers Resolution to close loopholes and give the law sharper teeth.
Fortunately, viable structural reform proposals already exist, having been introduced on a bipartisan basis in both chambers during the Biden administration. These bills are the National Security Powers Act in the Senate, introduced by Senators Chris Murphy (D-CT), Mike Lee (R-UT) and Bernie Sanders (I-VT), and title I of the National Security Reform and Accountability Act, introduced in the House in 2021 and 2022 by Rep. Jim McGovern (D-MA) with bipartisan support.
These bills substantially rewrite the War Powers Resolution. Though they have a few salient differences – and both are in need of some updating to take account of lessons learned in the second Trump administration’s spate of unauthorized wars – they are essentially companion bills that share many features.
Funding cut-offs for stronger enforcement
First, these bills would bar funding for any non-defensive hostilities undertaken without congressional authorization. As one of us wrote with Steve Pomper when the NSPA was first introduced in 2021, the automatic funds cut-off in these bills would go a long way toward remedying the current structural imbalance between the branches:
This turns the Constitution’s intended balance of powers on its head: “instead of a majority of Congress having the power to authorize the President to initiate the use of force, a supermajority is required to stop the President from doing so.”
The NSPA rights this balance by including an automatic funds cut-off (section 108) for any activities by United States forces that do not comply with its terms. It links the enforcement mechanism to another core congressional power — the power of the purse — and does not require a vote, let alone a supermajority in both houses, to take effect. And a funding cut-off “has the added benefit of being backed by the Anti-Deficiency Act, which makes it illegal to ‘make or authorize an expenditure or obligation exceeding an amount’ appropriated or funded for a specified purpose.”
Defining key terms
Second, both bills include definitions for key terms that were undefined in the text of the 1973 War Powers Resolution. Though legislative history should make clear that the executive’s interpretations of these terms have been unduly self-serving (removing the statute’s constraints on the president at the expense of Congress’s authority), nailing down definitions of terms such as “hostilities” and making clear what it means to “introduce” U.S. armed forces into hostilities are needed reforms to overcome the statutory gymnastics the executive has played across administrations since 1975.
Leaving intact necessary unilateral defense action but safeguarding against abuse
As former executive branch lawyers, we are aware that the president will sometimes need to use force in self-defense to repel an actual attack, or perhaps to rescue U.S. nationals from situations in which they face a concrete threat of imminent attack. These war powers reform bills recognize and leave intact the ability to act in real emergency situations, but “without allowing the use of truly defensive force… to turn into long-term entanglements or merge into other missions absent congressional involvement.”
Specifically, the NSRAA allows for short-term, defensive, unilateral military action by the president “when necessary to repel a sudden attack, or respond to a concrete, specific, and immediate threat of such a sudden attack, upon the territory, airspace, or waters of the United States, United States forces, or United States citizens.” (Very similar language is in section 102 of the NSPA). In doing so, the legislation strikes a balance. It does not impinge on the president’s long recognized constitutional authority to take truly defensive action in the immediate term. But it seeks to guard against unauthorized, elective operations merely characterized as defensive—actions that require congressional authorization–or those that might start out as defensive action but take on other missions over time. The automatic funds cut-off noted above ensures that the time limit for any such supposedly defensive action is adhered to.
This approach is both constitutionally sound and prudent. The framers of the Constitution, as well as the Supreme Court since the Prize Cases, recognized that the president has inherent constitutional authority even in the absence of congressional authorization to “repel sudden attack.” This is not, however, an inherent constitutional authority to wage open-ended or offensive conflict, but rather the authority to use interim defensive action until Congress can respond. In enacting the 1973 War Powers Resolution with its 60-day clock, a supermajority of Congress reinforced the well-understood principle that there are temporal limits to even supposedly defensive military actions undertaken by the president.
Shortening the “60-day termination clock”
By now it is well understood that the War Powers Resolution’s backstop requirement that the president terminate hostilities after 60 days unless authorized by Congress is not working as intended. Both the NSPA and NSRAA shorten the time limit for unilateral defensive action, creating a new 20-day default to “‘[r]emove the temptation for the Executive branch’ to engage in quick, unauthorized wars.”
Multiple factors militate toward reducing the window for unauthorized though ostensibly defensive action even further. Given the realities of modern transportation and telecommunications, the interval during which the president must act unilaterally to repel attack before Congress can respond should be brief.
In situations in which truly defensive action is undertaken, past practice indicates that an interval of under a week would be adequate. The two categories of such incidents are: (1) defensive operations that have become large-scale wars that were quickly authorized by Congress, and (2) smaller defensive interventions closer to the core of the president’s constitutional authority. Starting with the former, it is noteworthy that while U.S. armed forces at Pearl Harbor obviously acted in self-defense on Dec. 7, 1941 without waiting for any congressional action (literally to repel a sudden attack), Congress declared war on Imperial Japan the very next day. Similarly, Congress passed the 2001 Authorization for Use of Force within days of the 9/11 attacks—on Sept. 14, 2001.
In the second category, brief, defensive unilateral actions that are arguably comfortably within unilateral presidential authority have been undertaken by presidents of both parties in almost every administration since the enactment of the 1973 War Powers Resolution. These situations – operations such as evacuating embassies under threat when war breaks out or rescuing U.S. nationals from peril – necessitate truly rapid action by the executive, and sometimes within a specific window of operational opportunity that cannot be precisely predicted before it arises. But these operations tend to end as quickly as they begin.
A comprehensive review of all unclassified 48-hour reports filed under the War Powers Resolution compiled and analyzed in the War Powers Resolution Reporting Project at NYU’s Reiss Center on Law and Security illustrates this with real data. Of the nearly 40 reports that constitute “hostilities” (or imminent involvement of hostilities), and for which the purpose of the operations was responding to a threat, protecting U.S. nationals, protecting U.S. citizens or property, or conducting a rescue or hostage recovery, 30 were completed within 1-2 days. That is, before the 48-hour report was even filed. Of the remaining reports, several were for activity that Congress had already authorized or moved quickly to authorize (the 1991 and 2003 Iraq wars and the war in Afghanistan), or for which the executive branch subsequently claimed congressional authorization already existed (counter-ISIL operations that began in 2014). The tiny handful that remain were unauthorized hostilities in Panama, Yemen, and Iran that arguably were not in fact related to a need to act in immediate self-defense but were described as such in the president’s reports to Congress – these prove the point.
At bottom, limiting the interval for unilateral defensive action is prudent to prevent abuse. By shrinking the interval for any unauthorized action, Congress may deter further presidents from placing U.S. armed forces in harm’s way and thereby willfully creating the conditions under which self-defense might be invoked. (Bill Barr, then Deputy Attorney General, proposed such a “bootstrap” legal theory to President George H.W. Bush to justify waging the Gulf War without congressional authorization.) More generally, future administrations operating under a reformed War Powers Resolution may be tempted to recast offensive military actions as defensive in order to shoehorn them into the residual self-defense carveout. Shortening the deadline for ostensibly defensive unilateral action may discourage such gamesmanship.
Increased Transparency
The transparency forcing functions of the War Powers Resolution remain important. Although the information provided to Congress is often brief, most presidents comply with these requirements most of the time, and they serve a crucial function. That said, as explained in 2021, while there remains value in the current 48-hour reporting requirement, there is also a good deal of room for improvement that would strengthen the transparency-forcing functions of the WPR:
The NSPA strengthens the reporting requirements for situations of hostilities, defining much more clearly and thoroughly the information the president must provide to Congress.
It also fixes another problem with the current reporting framework, in which the Executive branch can essentially go dark after an initial 48-hour report (currently, no further reporting is required during the entire time period prior to the expiration of the termination clock). The NSPA solves this by requiring initial reporting within 48 hours of an introduction of U.S. forces into hostilities (or a situation where there is a serious risk of hostilities), followed by more thorough reporting within 7 calendar days unless the president certifies that the forces have been withdrawn (or the situation that triggered the requirement has otherwise ceased) and does not intend to reintroduce them.
While some further updating of these reporting provisions in the NSPA and NSRAA may be warranted today, they remain a valuable baseline for legislators.
Judicial Review
Unlike its Senate counterpart, the NSRAA would create a mechanism to increase the likelihood of judicial intervention in war powers disputes between Congress and the White House. It is currently extremely challenging to use the courts to enforce the provisions of the War Powers Resolution. Legislative reform of the 1973 law could increase the likelihood that the courts play a meaningful role in policing exercises of war powers.
Conclusion
The calamity of the Iran War is a stark reminder of why the Constitution assigns Congress the power to take the United States to war rather than leaving such momentous decisions to the whims of one person. Congress has taken a historic step to signal its opposition to Trump’s unauthorized and rudderless hostilities with Iran in H. Con. Res. 86. Blocking a floor vote on the NDAA was another welcome step. But now Congress must do more to practically curtail these continued hostilities and to prevent future abuses of the military by presidents acting unwisely and well outside of their authority.
The legislative branch can rein in executive unilateralism in all the ways catalogued here – it needs structural war powers reform to do so sustainably. And while there may not be enough votes to override a veto on wholesale reform legislation now, it is the perfect time to make the case to the American people that these reforms are needed, indeed long overdue, and to lay the groundwork for their eventual enactment into law.
