Is preemptive assassination the new Trump doctrine?

Was Qassem Suleimani's killing lawful? And why does it matter?

The episode raises intertwined questions of law, process, and policy. The Trump administration's case for assassinating Iran's top general last week in Baghdad is being hotly debated by the US Congress, where the House just passed a war powers resolution aimed at restraining the president's military action against Iran. While the facts are still emerging, most indications suggest that the strike was illegal. US officials had no business putting this illegal option on President Donald Trump's desk, even as an "extreme option" they expected the president would reject. The decision-making process was abysmal and ensured that the legal issues would not be properly vetted and that Congress would be denied its statutory and constitutional role.

As a matter of policy, Trump's unsubstantiated claim that Iran, having responded, is now "standing down" hardly vindicates his reckless action. Assassinating state leaders, provoking retaliation, then narrowly averting needless open warfare is not strategic success. This is especially true when the episode leaves Iran policy in a far worse place than it was five years ago when the previous administration negotiated a suspension of Iran's nuclear program. Most important, by using assassination as a tool of preemptive self-defense, the Suleimani strike raises the haunting question of whether Trump has resurrected the very doctrine that many thoughts had been wholly discredited by the disaster in Iraq.

Under current law, Trump had no business ordering the killing of one of the highest-ranking military leaders of a foreign state with which the United States was not at war. Before the strike, the United States had not engaged in armed conflict with Iran as a matter of international law. Nor can it be plausibly argued that Congress authorized the strike under a 2002 Authorization for Use of Military Force (AUMF) that was designed to authorize force to defend "against the continuing threat posed by Iraq" when the long-departed Saddam Hussein was Iraq's president. 

Suleimani undeniably orchestrated numerous proxy and terrorist strikes over many years. But unlike Osama bin Laden, who headed a nonstate terrorist group, Suleimani was de facto the second-highest-ranking official of a sovereign state. Like Adm. Yamamoto Isoroku, a Japanese military champion of the Pearl Harbor attack, Suleimani should only have been targeted as part of an ongoing armed conflict with Iran. If killing him was an intentional decapitation strike, it was tantamount to declaring war on Iran, which under the US Constitution's "declare War" clause required congressional consultation and participation. And if his premeditated killing was simply to eliminate him, not a necessary and proportionate response to address the imminent threat of attack by Iran, it was an assassination without legal basis, forbidden by a 43-year-old Ford administration executive order.  

Even if deemed a terrorist, Suleimani was a high-level state actor, against whom other sovereign states normally act with tools of sanction, diplomacy, and warning, not assassination. That he was head of the Quds Force of the Islamic Revolutionary Guard Corps, a US-designated foreign terrorist organization, does not make him a legitimate target. Trump defied precedent in April 2019 when he stretched that statutory designation to include an identified unit of a sovereign army. Suleimani was reportedly in Iraq on a diplomatic mission. How would Americans react if other countries designated SEAL Team 6 or Joint Special Operations Command as foreign terrorist organizations and then targeted them while training in foreign countries? And how are Americans made safer if their country kills the leader of a state military group with an established chain of command that ensures immediate elevation of a replacement empowered to order precisely the same attacks?

Most dubious is the Trump administration's effort to defend the strike under the international law doctrine of self-defense, falsely claiming to build on precedents from former President Barack Obama's time in office. The Suleimani strike was not a lawful targeted killing of the kind regulated by the Obama administration's well-publicized drone playbook. Obama administration policymakers and lawyers were acutely aware that preemptive assassinations start, rather than end, wars. And so, the Obama administration never assassinated a sovereign military leader as part of an offensive assault to promote regime change. If, like the Obama administration and the British government, the Trump administration claims that it acted in elongated self-defense because of Suleimani's past bad acts, it must produce and share with Congress, US allies, and the public its factual basis for four claims: first, that killing would prevent an imminent attack on US territory or critical American interests; second, that the attack was necessary because no lesser measure would have sufficed and the action would not escalate; third, that the attack was proportionate to the threat posed; and fourth, that in so doing, the United States adequately respected the territorial sovereignty of US-allied Iraq, where the strike occurred.  

While its briefings remain classified, the administration has apparently failed to produce evidence that Suleimani was about to launch an imminent attack to which the United States needed to give a proportionate response respectful of Iraq's sovereignty. Even Republican loyalist Sens. Mike Lee and Rand Paul found laughable the administration's classified briefing on the topic. And the New York Times' Rukmini Callimachi said that officials briefed on the classified evidence found the case for imminence "razor-thin" and saw "the reading of the intelligence as an illogical leap." Secretary of State Mike Pompeo's amorphous claim that Suleimani made "continuing efforts … to build out a network of campaign activities that were going to lead potentially to the death of many more Americans" gave no assurance that Trump met any of these legal prerequisites: imminence, necessity, proportionality, or respect for sovereignty. And Trump's listing of Iranian cultural sites—protected under international law from targeting by The Hague and the Geneva Conventions—would violate the fifth legal prerequisite of "humanity," which any government making such targeting decisions must take into account. 

Presidential subordinates should never present illegal options. And government officials sworn to uphold the Constitution and the rule of law have no authority to request, accept, or execute them. So why was US and international law so casually ignored? 

Simply put, bad process. The decision was taken abruptly at Trump's private Mar-a-Lago resort, without the careful interagency policy and legal process that accompanies a targeting decision fully vetted by National Security Council policymakers and agency lawyers. Neither short- nor long-term strategic consequences were vetted, nor did this irreversible decision consider any coherent vision of Iran policy. One former National Security Council staffer, Jonathan Stevenson, has chillingly reviewed the intra-executive branch process, testifying to a broader "abject dysfunction and deterioration of the national security process under Mr. Trump." And the interbranch process, particularly prior congressional reporting or consultation, seems to have been limited to Trump's casual Florida conversation with Republican Sen. Lindsey Graham, who is not a member of the so-called Gang of Eight Senate leaders ordinarily consulted about sensitive intelligence matters. Mar-a-Lago country club members reportedly had more warning than the highest congressional leaders.

Nevertheless, Trump's supporters justify the strike as good policy because a bad actor has now been neutralized. But keen observers—such as former senior national security officials Susan Rice and Richard Haass, among others—have all shown why even if somehow deemed lawful, the decision was still awful national security policy that made the United States less safe in the world. Trump's premature claim that Iran is "standing down" after a largely symbolic retaliatory strike cannot be credited when we don't know what other retaliatory attacks, cyber or kinetic, still await the United States. 

Beyond law and process, in an age of drone strikes and targeted killings, what's wrong with including preemptive assassination as a policy option? Assassination is forbidden by US law because it starts wars and quickly becomes deeply destabilizing. The same rationale used to kill Suleimani could be used tomorrow against North Korea's Kim Jong Un, Syria's Bashar al-Assad, or rogue Venezuelan President Nicolás Maduro. Because reciprocity lies at the heart of international law, how long would it be before hostile foreign powers start invoking the same rationale to target America's own bellicose officials?

Law, policy, and process are deeply interrelated. Law locks in the lessons of policy, to provide predictability and accountability. Legality and sound process tend to promote a more stable policy, while illegality and bad process foster policy disaster. Legal compliance and good national security process enable multilateral cooperation, accountability, and political agreement about sensitive policies between the executive branch and Congress. But illegality combined with shoddy process breed cascades of illegality that strain the relationship between the president, Congress, and US allies; promote executive and US unilateralism; and enhance secrecy and coverup.

Witness the George W. Bush administration's disastrous embrace of illegal torture. The Justice Department's infamous 2002 torture memo said, in effect, that if the United States could attack in preemptive self-defense, it can torture people in preemptive self-defense. The same administration invoked arguments based on preemptive self-defense to put troops into the Philippines, to gear up for its Iraq campaign, and to assert in its national security strategy paper a customary right of preemptive self-defense.

But the absence of weapons of mass destruction in Iraq debunked those claims. Two Bush administration maxims best illustrate the perils of preemptive war. Combine a maxim then-Defense Secretary Donald Rumsfeld notoriously embraced, "absence of evidence isn't evidence of absence," with then-Vice President Dick Cheney's so-called One Percent Doctrine: "Even if there's just a 1 percent chance of the unimaginable coming due, act as if it is a certainty." So even if there's no smoke, assume there's a fire, which justifies attacking preemptively. But preemptive attacks are not meaningfully restrained by notions of necessity or proportionality. If you think someone will attack with intent to kill, your best bet is to kill them first, à la Pearl Harbor. When that mindset prevails, the evidence yields to hunches and the twisting of evidence, which is what helped create the rationale for intervening in Iraq in 2003 with overwhelming force to stop nonexistent weapons of mass destruction.

Under traditional international legal doctrine of self-defense, an aggressor must take unambiguously aggressive first steps before the object of their aggression can legally respond in self-defense. But if we change the law to authorize a nation to respond not just to perceived threats, but to mere premonitions thereof, and then to inklings of premonitions that one's adversary might misperceive motives, hard evidence is displaced by conjecture or outright lies. Down this hall of mirrors lies a doctrine that assumes necessity, then authorizes disproportionate use of force to "shock and awe" a potential attacker into submission. 

We cannot let Trump and his administration launch a new forever war against Iran and its various proxies by using vague Twitter claims as weapons of mass distraction. And Americans should hold Pompeo strictly to his vow, oft-repeated since the strike, that "every action" the United States takes "will be consistent with the international rule of law." By their very nature, claims of preemptive war turn on "trust me" actionable intelligence. To prevent a replay of Iraq, Congress, the media, and the public must continue their intensive detailed scrutiny of Trump's factual basis for his claim of imminence. What factual basis did Trump have for thinking that Suleimani was planning an imminent 9/11-type operational attack on the US territory or interests? Without such information, it was illegal to even consider killing Suleimani as a policy option; but if such information existed, Congress was legally required to have seen it. Either way, the strike seems to have been illegal.

This also means rejecting Trump's and Pompeo's simplistic flattening of the issue into a false bipolar choice between "attack" or "do nothing." Even if, as Pompeo claims, the risk of US nonaction was greater than the risk of action, the action taken did not demand unilateral military force. It could instead have called for a third way: disarming Iran without pre-emptive attack through a multilateral strategy of disarmament that would include diplomacy, transparency, containment, and enhanced sanctions. This third way should sound familiar, as precisely such a process led the Obama administration to conclude the 2015 Iran nuclear deal. By reflexively discarding that deal without a safety net, Trump predictably triggered a cycle of tit-for-tat retaliation, and to escape it, he now ironically calls for new multilateral negotiations years later that could at best produce an inferior version of that accord.

Despite its impeachment stalemate, Congress must demand the testimony, under oath, of those officials who shaped the options and argued for killing Suleimani. At the same time, legislators should force Trump to clarify America's near- and long-term goals in Iran and Iraq. As debate shifts to the Senate, that body should legislate against further Iran escalation by enacting Rep. Elissa Slotkin's resolution, recently adopted by the House under the War Powers Resolution's expedited procedures. Congress should also enact Rep. Ro Khanna's bill denying funding to any offensive actions in Iran. As described elsewhere, Congress must repeal the now-obsolete 2002 Iraq AUMF and promptly move to hearings on the war powers bill offered by Sen. Tim Kaine, incorporating sound ideas from a related bill offered in the last Congress by Sen. Jeff Merkley. 

The House's impeachment of Trump over his national security abuse in Ukraine teaches that the current president is a national security threat. The Suleimani strike confirms that Congress cannot give an impeached yet impetuous, uninformed yet unchecked president carte blanche to wag the dog of war in Iran. 

Harold Hongju Koh, is a professor of international law at Yale Law School and a founding editor of Just Security. He was legal advisor at the State Department from 2009 to 2013, and assistant secretary of state for democracy, human rights, and labor from 1998 to 2001.