While President Donald Trump opted not to launch an airstrike against Iran last week in response to the shoot-down of a U.S. drone, he’s made clear that he still might order one, and that he doesn’t think he needs congressional authorization to do it. “I do like keeping them abreast, but I don’t have to do it legally,” he told the Hill in an interview on Monday. Democratic congressional leaders disagree, including House Speaker Nancy Pelosi, who said last Friday that “hostilities must not be initiated without the approval of Congress.” Sen. Tim Kaine, a leading voice on these issues, has been more explicit in recent weeks: “Let me make one thing clear: The Trump Administration has no legal authority to start a war against Iran without the consent of Congress.”
But as much as I oppose strikes on Iran, and as much as I think Congress should play a much greater role in oversight of military action, it seems hard to argue that Trump wouldn’t have the legal authority to carry out the kind of airstrike that was reportedly considered last week, at least under the interpretation of executive power advanced by Barack Obama’s administration.
Article I on the Constitution gives Congress the right to declare war—as Democratic Rep. Ro Khanna, a war powers critic, noted in a tweet Tuesday—but Article II designates the president as “Commander in Chief of the Army and Navy,” which presidents of both parties have long argued grants them the authority to launch certain military actions without congressional authorization. Different administrations have advanced different specific arguments about what sort of actions this authority applies to.
In 2011, Obama—who, as a former constitutional law professor, had taken a much narrower view of executive power before coming to office—ordered airstrikes in Libya, under the auspices of NATO, initially to prevent what many feared was an imminent massacre of civilians by Muammar al-Qaddafi’s forces in Benghazi. The goals of the air campaign eventually expanded after Qaddafi was overthrown.
In justifying the decision to not seek congressional authorization for the Libya campaign, Obama’s Office of Legal Counsel argued at the time that there was a two-part test to determine whether the president had the authority to order the strikes on his own: The action in question had to “serve sufficiently important national interests,” and it must not be “sufficiently extensive in ‘nature, scope, and duration’ to constitute a ‘war.’ ” This justification remained circumscribed, though, by the 1973 War Powers Resolution. Passed in the wake of the Vietnam War, the resolution states that the president has to ask Congress for authorization if hostilities last longer than 60 days. As Obama spokesperson Jay Carney put it at the time, “these constrained and limited operations do not amount to hostilities under the War Powers resolution.”
Ironically, given the current president’s ongoing crusade to obliterate Obama’s foreign policy legacy, the Trump administration cited the Obama OLC’s legal analysis and its two-part test in 2018 when explaining the legal framework for its missile strikes in Syria, launched in response to the Bashar al-Assad regime’s use of chemical weapons.
Scott Anderson, a former legal adviser at the State Department who is now a fellow at the Brookings Institution, told me in a phone interview, “You saw the Trump administration basically take up the Libya test and apply it to the Syria airstrike. It was a really telling step. I think they found it persuasive, and I also think they found it not particularly restraining. It gives the president a huge amount of authority to do anything short of a massive invasion or using lots of ground troops.”
A “national interests” argument actually seems stronger in the case of Iran than in Libya or Syria. Whatever their crimes, neither Libya nor Syria had attacked U.S. citizens or facilities. Iran has not only downed a U.S. drone. (Iran says the drone was in its territory, but let’s stipulate for the sake of argument that it was flying over international waters, as the U.S. maintains.) The nation’s proxies in Iraq have been accused of launching rocket attacks near U.S. diplomatic facilities, endangering American personnel. The U.S. previously justified military strikes with the rationale of preventing regional instability. Alleged recent Iranian-directed attacks on oil shipping vessels and Saudi energy facilities would seem to fit that bill.
So, a one-time strike on a handful of Iranian targets like the one the Trump administration reportedly contemplated seems entirely in keeping with the Libya precedent, though Obama’s “sufficiently extensive” test would rule out Trump mounting a full-scale ground invasion.
But the Article II, two-part test argument is not the only legal justification that the current administration is advancing. It’s reportedly also arguing that the trusty old 2001 Authorization for the Use of Military Force, passed by Congress to target the perpetrators of 9/11, but later used in conflicts from Syria, to Yemen, to Niger, could apply to a strike on Iran. Rep. Elissa Slotkin, a former CIA analyst and Pentagon official, said in a recent House Armed Services Committee meeting that in a closed-door briefing, Secretary of State Mike Pompeo delivered a formal presentation “on how the AUMF might authorize war on Iran” and that Pompeo “referenced a relationship between Iran and al-Qaida.”
This is a stretch, even by the standards of the very stretchy AUMF. Iran did grant refuge to al-Qaida members, including some members of Osama bin Laden’s family, after the U.S. invasion of Afghanistan in 2001, sometimes keeping them under loose house arrest, but that was never more than an arrangement of convenience. Al-Qaida regards Shiites—which the overwhelming majority of Iranians, including the country’s leaders, are—as heretics, and the two back opposing sides in regional conflicts, including the wars in Yemen and Syria. Moreover, the idea that a member of Congress voting for the use of force against al-Qaida in 2001 was also signing up for a war against Iran in 2019 is plainly absurd.
So why make this AUMF case at all when the argument that Trump could act under his constitutional executive powers seems so much more robust? Well, it’s possible some Trump officials are looking beyond the sort of limited authority that the Libya and Syria precedents provide. National security adviser John Bolton has long favored regime change in Iran, and Pompeo has sometimes seemed to as well.
The AUMF “is an argument that gives them much more operational flexibility,” says Anderson. Is there anything Congress can do about this? On Tuesday, Khanna and Republican Rep. Matt Gaetz introduced an amendment to the National Defense Authorization Act that would deny funding to any military action taken against Iran without congressional authorization. It’s not clear if the amendment will be adopted or if Trump would veto it. He grumblingly signed the 2018 NDAA, which included language barring him from removing U.S. troops from South Korea or recognizing Crimea as part of Russia.
This may not be the most elegant way to exercise oversight of the president. But given that successive administrations have been able to push their executive authority to wage war to the absolute hilt, the tide seems unlikely to turn unless Congress takes that power back.
Support work like this for just $1
Slate is covering the stories that matter to you. Become a Slate Plus member to support our work. Your first month is only $1.