The debate over the legal authority for the lethal strike against Qassem Soleimani has once again brought attention back to the 2002 Authorization for the Use of Military Force Against Iraq. Best referred to as the “Iraq AUMF,” it should not to be confused with the 2001 Authorization for the Use of Military Force which is directed to those responsible for the September 11 attacks. In pushing back against bipartisan claims that the President should have obtained congressional authorization for the strike, the White House has relied not only on the President’s inherent Article II power as commander in chief, but on the Iraq AUMF as well. On Wednesday, for example, a delegation of cabinet members told Congress that it was that statute that provided the authority for the President to engage in acts of war against Iran like the targeted killing of Iran’s most senior military official.

We aim to explain why this reasoning is false as a matter of law. As importantly, because neither the 2001 AUMF nor the Iraq AUMF already authorizes the offensive use of military force against Iran, it is clear that President Trump must turn to Congress before he can engage in any offensive military actions against Iran going forward.

I. The Text of the Iraq AUMF

As the title of the Iraq AUMF makes clear, the statute is for the “use of military force against Iraq,” not Iran. The operative provision—section 3(a) of the statute—is no less explicit:

The President is authorized to use the Armed Forces of the United States as he determines to be necessary and appropriate in order to—(1) defend the national security of the United States against the continuing threat posed by Iraq; and (2) enforce all relevant United Nations Security Council resolutions regarding Iraq.

Whatever threat Iran might pose to the United States, even in Iraq, it can hardly be said to be a threat “by Iraq.” Nor are there relevant Security Council resolutions regarding Iraq that could justify such a use of force. It is impossible to imagine that Congress in 2002 would have thought that it was authorizing the use of force against another nation’s armed forces besides Iraq’s; the 2002 Congress would demand any President return for a new authorization before launching military operations against another state. That ought to be the end of the matter.

II. Who is “Iraq”?

The Soleimani strike is not the first time we’ve seen the argument that the Iraq AUMF authorizes the use of force against actors other than the Iraqi government. For instance, in 2014, Jack Goldsmith argued that the 2002 AUMF “almost certainly” authorized the use of offensive military force against the Islamic State in Iraq insofar as the statute authorized the President to defend against “the continuing threat posed by Iraq.” Such text, Jack argued, encompassed not only the WMD-specific threat posed by the Saddam Hussein regime at the time the statute was passed, but also any new threats that would later emerge out of the geographic space of Iraq—whether Congress could have foreseen them at the time of the authorization or not, within the same decade or not, and whether or not the threat was “by” Iraq. As he wrote:

That text gives the President the discretion to determine when the use of the U.S. Armed Forces is necessary and appropriate to defend U.S. national security against the continuing threat posed by Iraq (not the government of Iraq, not Saddam Hussein, but Iraq), and authorizes the President to use those forces in that circumstance.  It is not at all hard to interpret this statute to authorize the President to use force today to defend U.S. national security from the threat posed by the ISIS-induced collapse of Iraq.

Even Jack’s argument, with which we took serious issue, depended upon the claim that U.S. national security would have been jeopardized by the ISIS-induced collapse of Iraq—and so using force against ISIS was necessary in order to mitigate the threat that an Iraq governed by ISIS would have posed. We didn’t buy it (in part because we argued the 2002 AUMF had become defunct), but we at least see the reasoning.

Here, in contrast, there is no plausible argument that attacking Soleimani, personally—or Iran, more generally—was necessary to protect the United States from the threat that would be posed by Iraq. Its proxy efforts notwithstanding, Iran is a distinct sovereign entity that is not directly seeking to occupy Iraq or forcibly take over the Iraqi government.

There used to be a fairly clear consensus on the non-application of the AUMF to Iran until this most recent turn by the Trump administration. Senior Obama officials wrote in an Expert Backgrounder, “there is no viable argument that [the 2002 AUMF] authorizes force against Iran.” In his nomination for Defense Secretary in July 2019, then-Secretary of the Army Mark Esper testified that the 2002 AUMF could not authorize the use of military force against Iran. And in June 2019, the administration informed Congress that “the Administration has not, to date, interpreted either AUMF as authorizing military force against Iran, except as may be necessary to defend U.S. or partner forces engaged in counterterrorism operations or operations to establish a stable, democratic Iraq” (emphasis added to highlight the exception).

Assuming that exception is legally valid (a big assumption), it does not appear to be relevant to the Soleimani strike. First, if the strike were to defend the U.S. forces engaged in counterterrorism operations in Iraq, the administration would have presumably invoked the 2001 AUMF as well. Second, as Tess Bridgeman wrote, “justifications that senior U.S. officials such as the Secretary of State have given — such as Soleimani’s threat to U.S. diplomats and citizens in other parts of the region — have no connection to the U.S. counter ISIS operations.”

What about operations to establish a stable, democratic Iraq? On the past occasions when the United States used force against militia in Iraq under the 2002 AUMF, it was when those groups were part of an insurgency against the US-supported government in Baghdad. But today’s situation is the reverse. Some of those same groups – including the Iranian-backed militia – have since been formally incorporated into the Iraqi military — and U.S. forces have fought alongside them in battling ISIS.

Unlike the use of force against militia during the Iraqi insurgency (pre-2011) and against ISIS (2014-present), the Trump administration’s military strike against Iran inside Iraq is entirely antithetical to supporting a democratic, stable Iraq, both in practice and formally. Just look at the Iraqi government’s strong reaction to the strikes.

Six years ago, we thought it was quite a stretch to argue that the Iraq AUMF could be extended to encompass the use of force against ISIS. But it is beyond any reasonable interpretation of that statute to argue that it applies to uses of force against Iran in Iraq. If, for whatever reason, the Trump administration wants to use additional, offensive military force against Iran, whether in Iraq or elsewhere, it needs to receive new statutory authorization from Congress.


Image: Nicholas Kamm/AFP via Getty Images