Trump Administration's Iran Policies Raise Questions About the Executive's Authority to Use Force Against Iran

In the face of rising tensions between Iran and the United States, some members of Congress have urged the Trump administration to clarify whether it believes it has congressional authorization to use force against Iran.¹ In June of 2019, the U.S. State Department issued a letter stating that it had not “to date” interpreted either the 2001 or the 2002 Authorization for Use of Military Force (2001 AUMF and 2002 AUMF, respectively) “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.”²

In May of 2019, the Trump administration sent an air carrier strike force and a bomber strike force to the Middle East “to send a clear and unmistakable message to the Iranian regime that any attack on United States interests or on those of our allies will be met with unrelenting force.”³ On June 17, Acting Secretary of Defense Patrick Shanahan authorized the deployment of 1,000 additional troops to the Middle East in response to “the reliable, credible intelligence we have received on hostile behavior by Iranian forces and their proxy groups … .”⁴ After the troop deployment, a bipartisan group of six senators sent a letter to President Trump inquiring about the relationship of the deployed troops’ mission to Iran:

Given that growing risk, we want to reiterate that, as of this date, Congress has not authorized war with Iran and no current statutory authority allows the U.S. to conduct hostilities against the Government of Iran. To that end, we expect the administration to seek authorization prior to any deployment of forces into hostilities or areas where hostilities with Iran are imminent … . Article One, Section 8 of the United States Constitution provides Congress the exclusive power to declare war. It is critical that Congress fully retain and enforce this authority.⁵

Even before this additional deployment, the administration had faced questioning regarding a potential war with Iran. After the designation of the Iranian Islamic Revolutionary Guards Corps as a foreign terrorist organization,⁶ Senator Rand Paul asked Secretary of State Mike Pompeo during testimony at the Senate Foreign Relations Committee if he believed that the 2001 AUMF applied to Iran.⁷ Pompeo replied, “I'd prefer to just leave that to lawyers.”⁸ After Paul pressed him for a direct response, Pompeo stated:

The legal question I will leave to counsel. The factual question with respect to Iran's connections to Al Qaeda is very real. They have hosted Al Qaeda. They have permitted Al Qaeda to transit their country. There's no doubt there is a connection between the Islamic Republic of Iran and Al Qaeda. Period, full stop.⁹

In response, Paul stated, “I can tell you explicitly you have not been given power or authority by Congress to have war with Iran,” to which Pompeo did not reply.¹⁰

At a House Foreign Relations Committee hearing on June 19, Chair Ted Deutch asked the State Department's Special Representative for Iran Brian Hook if the administration believed that Al Qaeda operatives transiting through or living in Iran were sufficient grounds for the use of force in Iran under the 2001 AUMF.¹¹ Hook reiterated that it was not the policy goal of the administration to seek a military engagement with Iran but stated, “If the use of military force is necessary to defend U.S. national security interests, we will do everything that we are required to do with respect to Congressional war powers and we will comply with the law.”¹² When pushed on the point, Hook referred Deutch to the State Department's Office of the Legal Adviser.¹³

The day after Hook's testimony, Iran downed an unmanned U.S. drone.¹⁴ Iran subsequently submitted a letter to the Security Council of the United Nations reporting the downing of the U.S. drone and claiming that its actions were justified under Article 51 of the Charter of the United Nations because the drone “engaged in a clear spying operation.”¹⁵ Iran asserted that the drone “entered into the Iranian airspace where the Islamic Republic of Iran … targeted the intruding aircraft … .”¹⁶ A U.S. press release announcing the incident stated that the drone was operating over international waters thirty-four kilometers from the Iranian coast and that “Iranian reports that this aircraft was shot down over Iran are categorically false.”¹⁷

On the following day, June 21, Trump announced that he had ordered and then cancelled retaliatory strikes against Iran because the strikes would not have been “proportionate to shooting down an unmanned drone.”¹⁸ The White House and the Pentagon did not further discuss these potential strikes on the record.¹⁹ While Trump cancelled physical strikes, media reports indicated that he did authorize certain cyberattacks against Iran.²⁰

On June 25, Deutch, as well as House Foreign Affairs Committee Chairman Eliot Engel, submitted a letter to the Acting Legal Adviser for the State Department Marik String requesting “[a]ny and all legal analysis, whether contained in electronic documents, emails, or hard copy, concerning, relating, or referring in any way to whether the 2001 or 2002 AUMFs are applicable to any actions that could be undertaken by the Executive Branch in or against the Islamic Republic of Iran.”²¹

The response from the State Department on June 28 came not from the Acting Legal Adviser, but rather from Mary Elizabeth Taylor, the assistant secretary of state for legislative affairs. She did not produce any documents in response to the request from Deutch and Engel, but rather stated in her letter:

The Department of State has great respect for Congress's role in authorizing the use of military force. As Secretary Pompeo has noted, the Administration's goal is to find a diplomatic solution to Iran's activities, not to engage in conflict with Iran. Moreover, 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.

President Trump has expressed the U.S. willingness to negotiate with Iran. No one should be uncertain about the United States’ desire for peace or a readiness to normalize relations in the event the United States and Iran reach a comprehensive deal. As Special Representative for Iran and Senior Policy Advisor to the Secretary of State Brian Hook testified to your Committee on June 19, 2019, the Administration has implemented an unprecedented maximum pressure campaign focused on Iran with two primary objectives: first, to deprive the Iranian regime of the money it needs to support its destabilizing activities, and second, to bring Iran back to the negotiating table to conclude a comprehensive and enduring deal as outlined by Secretary Pompeo in May 2018.²²

Neither her letter nor the inquiry to which she was responding discussed the conditions under which the president would have the independent constitutional authority to use force against Iran if neither the 2001 AUMF nor the 2002 AUMF were applicable.²³

On July 18, approximately a month after the downing of the U.S. drone, Trump announced that the American military had destroyed an Iranian drone located over international waters in the Strait of Hormuz.²⁴ Trump described the act as one of self-defense, asserting that the drone had approached an American vessel and ignored repeated warnings.²⁵ Unlike Iran, the United States does not appear to have submitted an Article 51 letter to the Security Council describing its action. Iran denied that it had lost any of its drones.²⁶

In addition to the tensions described above, relations between the United States and Iran worsened on other fronts during the summer of 2019. The Trump administration built upon the vast set of sanctions it had already imposed on Iran by implementing sanctions designed to target Iran's metals industry,²⁷ and by adding sanctions directed at the Office of the Supreme Leader of Iran.²⁸ In early July, meanwhile, Iran exceeded the uranium enrichment limits set out in the 2015 Joint Comprehensive Plan of Action, justifying this action by pointing to the earlier decision of the United States to withdraw from this commitment and reimpose sanctions.²⁹ Iran has also warned that it could stop all energy exports through the Strait of Hormuz if sanctions relief is not forthcoming.³⁰ In September of 2019, a drone attack inflicted major damage on Saudi oil production facilities. Iran denied carrying out the strike, but Pompeo, among others, deemed Iran responsible and warned of consequences.³¹