On Sept. 2nd, the Trump administration announced what it described as a “lethal strike” against an alleged drug smuggling vessel in the Caribbean. In a post on social media accompanied with a video of the strike, President Donald Trump stated that the attack was “against positively identified Tren de Aragua Narcoterrorists.” Trump also noted that Tren de Aragua had previously been designated as a foreign terrorist organization (FTO). The social media post also asserted that the strike had occurred in international waters and killed “11 terrorists.”

Although the facts are still emerging, the Trump administration’s extraordinary lethal attack on this purported smuggling vessel – and its vow that the strike was a start of a campaign – raise a number of significant potential legal issues. And even apart from these legal concerns, the strike constitutes a deeply troubling gratuitous use of the military that resulted in the unnecessary killing of 11 individuals. ......

A U.S. president may direct the use of military force pursuant to either (1) a congressional authorization for the use of force/declaration of war or (2) inherent authority under Article II of the Constitution, typically as commander in chief of the U.S. military. The scope of the president’s authority to direct the use of force under Article II in the absence of congressional authorization is contested. Although there is broad agreement that the president may use force to repel “sudden attack,” the U.S. executive branch has taken a much more expansive view of the president’s unilateral war powers.

Here the Trump administration will almost certainly rely solely on Article II of the Constitution as the source of authority for the attack on this vessel. Despite labelling the targets “narcoterrorists,” there is no plausible argument under which the principle legal authority for the U.S. so-called “war on terror”—the 2001 Authorization for the Use of Military Force—authorizes military action against the Venezuelan criminal entity Tren de Aragua.

Under the executive branch’s two-prong test for when a president may use force without congressional authorization, the contemplated operation must advance an important “national interest” and must not amount to “war in the constitutional sense,” which the Department of Justice’s Office of Legal Counsel (OLC) has recognized as an outer limit on the president’s unilateral warmaking authority. That said, OLC precedent marks out remarkably wide latitude, with the first prong in particular having been critiqued as being unconstraining, and it is not clear whether it would have limited the president in this instance even assuming OLC advice was sought before the strike took place.

Further, though Trump and others in his administration have emphasized the prior designation of Tren de Aragua as an FTO, such designation does not by itself convey authority to use force. Nonetheless, such FTO designations are widely and mistakenly perceived as authorizing such action within the executive branch. Thus, designation of Tren de Aragua and a number of other Latin American criminal entities as FTOs in February foreshadowed this week’s attack in the Caribbean, despite providing no actual legal authority for it.