Since the United States conducted a military strike on various targets associated with the Syrian government’s chemical weapons program last week, prominent voices in the legal community have questioned the legal bases for the Trump administration’s decision. One part of this discussion has focused on whether there is any domestic legal authority that would permit the strike. However flimsy the Trump administration’s explanation may be, President Donald Trump offered one to Congress on Sunday, invoking constitutional authority.
On the international law front, the Trump administration has been mostly silent, with the president’s statement on Sunday referring to no international legal authority. Yet during a House Armed Services Committee hearing last Thursday—before the strike occurred—Defense Secretary James Mattis flirted with an idea grounded in international law: self-defense. The only problem was that his description of self-defense was profoundly flawed.
As Oona Hathaway and Jack Goldsmith recently explained, the U.N. Charter “strictly prohibits the use of force subject only to exceptions for consent, self-defense, or Security Council authorization, none of which are implicated here.” During the congressional hearing on Thursday, Mattis attempted to explain the legal authority for a prospective strike.
Though it was admittedly unclear whether Mattis was trying to address the domestic or international element of the two-part legal inquiry, or both, he nonetheless articulated a theory that loosely resembled self-defense:
“We have forces in the field, as you know, in Syria, and the use of chemical weapons in Syria is not something that we should assume that, well, because he didn’t use them on us this time, he wouldn’t use them on us next time…Protection of our forces—I don’t think we have to wait until they’re under chemical attack when the weapons are used in the same theater we’re operating in.”
At one point, he also acknowledged that the path of U.N. Security Council authorization was untenable: “If Russia prevents the United Nations from dealing with it, we can sit acquiescent, or we can do something about it.” This suggests that Mattis was mindful of international law, not just domestic law, which he also discussed during the hearing. And on Tuesday, after the strike, Mattis stated that the U.S., along with the United Kingdom and France, “did what we believe was right under international law,” but he did not specify a legal basis for that claim.
Yet when Mattis seemingly did try to offer an international legal basis last Thursday, the conception of self-defense he described was not actually self-defense, which would have required an attack on U.S. forces by Syrian government forces. It wasn’t even anticipatory self-defense, which would have been legal and would have required that an attack was “imminent and unavoidable.” Rather, the idea explained by Mattis amounted to a preventive strike based on a highly speculative threat. As Scott Sagan and Allen Weiner bluntly explained in a New York Times op-ed earlier this month—in rebutting National Security Adviser John Bolton’s recent argument that such a strike against North Korea would be legal—a preventive strike is “aggression” and therefore illegal.
That Mattis’ reasoning before Congress last week echoed, or expanded upon, Bolton’s faulty preventive strike approach is also concerning for what it might foreshadow. What might it mean if this outlook is applied to North Korea and its nuclear weapons program, for example? In short, if Mattis’ reasoning is at all indicative of the Trump administration’s national security calculus moving forward, and if it’s fused with Bolton’s own views, it portends some plainly terrifying scenarios.
To be fair, Mattis’ self-defense remark may have simply been an impromptu or extemporaneous mistake by a non-lawyer in the flurry of a congressional hearing. Mattis did, after all, demonstrate caution in other ways—by reportedly arguing for a more limited strike against targets connected to Syria’s chemical weapons program instead of a more aggressive version supported by Bolton, a battle Mattis won, and reportedly encouraging Trump to secure congressional authorization prior to the strike, a battle Mattis lost. (On Wednesday, both the White House and Mattis denied that he’d advocated for congressional authorization.) It remains to be seen how Trump might resolve potential clashes in the future between Mattis and Bolton, who, unlike his predecessor, reportedly “is not expected to defer to the defense secretary.” But if the administration—with or without Mattis’ support—is, in fact, contemplating or embracing such a dangerous and legally unmoored perspective on preventive strikes, it should be made fully clear to our political representatives, expert communities, and the public writ large so they can at least contest and debate it.
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