On Sept. 2, the U.S. Navy conducted a strike on a speedboat in the Caribbean, killing eleven people aboard the vessel. The strike occurred, according to President Donald Trump, after U.S. forces “positively identified Tren de Aragua Narco terrorists … transporting illegal narcotics, heading to the United States.” Tren de Aragua (“the train of Aragua”) is a Venezuelan transnational criminal organization involved in a range of serious crimes across Latin America and in the United States, including drug trafficking, extortion, and violent assaults. Relatedly, the administration has accused Venezuelan President Maduro of facilitating drug trafficking and offered a $50 million reward for his arrest. Indeed, White House Press Secretary Karoline Leavitt has stated that U.S. policy maintains that the “Maduro regime is not the legitimate government of Venezuela. It is a narco-terror cartel,” a position reflected in the president’s Alien Enemies Act Proclamation, which says “the result is a hybrid criminal state.”
The day after the strike, Secretary of State Marco Rubio explained why the United States launched the operation.
The United States has long – for many, many years – established intelligence that allow us to interdict and stop drug boats, and we did that. And it doesn’t work. Interdiction doesn’t work because these drug cartels – what they do is they know they’re going to lose two percent of their cargo. They bake it into their economics. What will stop them is when you blow them up, when you get rid of them…. And it’ll happen again…. [T]he point is the President [of the] United States is going to wage war on narcoterrorist organizations.
On Sept. 4, Trump followed up with a War Powers notification to Congress offering a similar justification.
The strike operationalized an administration policy on counter-drug efforts that appears to be a transformation of the rhetorical “war on drugs” into an actual war on narcotics organizations. For instance, two days after assuming office, Trump issued an Executive Order designating narcotics cartels and other organizations as “foreign terrorist organizations and specially designated global terrorists” that “pose an unacceptable national security risk to the United States [and] …threaten the stability of the international order in the Western Hemisphere.” According to The New York Times, the president has issued a classified directive that the military is authorized to use force against such drug cartels in Latin America.
The purported international law basis for the operation appears to be self-defense. Rubio, for example, has asserted that the “president has a right to eliminate immediate threats to the United States,” while a White House spokesperson stated that the attack was “conducted against the operations of a designated terrorist organization and was taken in defense of vital U.S. national interests and in the collective self-defense of other nations.” I have also heard speculation that, aside from self-defense, the purported existence of an armed conflict with Tren de Aragua provides a legal basis for the U.S. operations against the group.
In this essay, I offer my views on two narrow international law issues that have been the focus of discussion regarding the incident. The first is whether the right of self-defense in the jus ad bellum (the law governing the resort to force by States as an instrument of national policy) is even available to justify forcible actions directed at groups involved in drug trafficking. As will be explained, I see no basis for forcible actions on this basis unless they engage in violent acts against the United States. I will also ask when a State needs to rely on the right of self-defense to justify forcible actions.
The second topic being discussed as a result of the strike is whether drug trafficking can qualify as an “armed conflict” with the State into which the drugs are being transported. I conclude that under the law of armed conflict (LOAC), drug trafficking and other drug-related actions, standing alone, cannot trigger either an international or non-international conflict. Others have grappled with these and other related topics, and I commend their work to readers in drawing their own conclusions (e.g., Finucane; Anderson; Nevitt; Pedrozo; Deeks and Waxman; Redaelli and Arévalo).
Before proceeding to the analysis, I would like to offer one crucial caveat. The strike and proposed operations raise a slew of international law issues with which I am not dealing, for I want to zero in on those gaining traction on this side of the Atlantic. Of particular relevance are the prohibitions and obligations of international human rights law. In that regard, I note that, as explained in the U.S. Army’s 2024 Operational Law Handbook, the United States shoulders various treaty and customary law human rights obligations that govern its activities, including during armed conflict (ch. 4). This is a complex subject that I leave to others with greater expertise. Still, the prospect of conducting lethal strikes abroad, especially outside armed conflict, undeniably implicates human rights law. Indeed, I believe it may well be the most relevant body of law in many of these situations. Accordingly, my analysis is without prejudice to any U.S. obligations under that or any other body of law.
Self-Defense
Self-defense is a customary international law right reflected in Article 51 of the UN Charter. It empowers States to use force that would otherwise violate the Charter’s Article 2(4) prohibition on the use of force, as well as that article’s customary law counterpart. Article 51 provides that “[n]othing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security” (see Dinstein, Gill and Szabó, and Ruys for comprehensive treatment of the right). As is apparent from the text, the fulcrum upon which the right sits is the qualification of the action(s) to which a State’s use of force responds as an “armed attack.”
Qualification as an Armed Attack:
To qualify as an “armed attack,” a drug cartel’s activities must have a transborder element (Tallinn Manual 2.0, p. 340). Thus, international law self-defense is inapplicable to operations against purely domestic drug gangs. But since the transnational criterion is by definition satisfied by drug cartels operating from abroad, the key question for our purposes is whether the shipment of drugs into a State (and related non-violent actions) is the type of activity that qualifies as an armed attack.
In its Paramilitary Activities judgement, the International Court of Justice ICJ explained that an “armed attack” is the “most grave form” of “the use of force,” as the latter term is understood in the context of Article 2(4) (para. 191). By contrast, the United States, incorrectly in my view, takes the position that all uses of force are equally armed attacks (DoD Law of War Manual, §1.11.5.2; Taft, p. 300). Despite the differing approaches, the common ground is that an action that fails to qualify as a “use of force” cannot be an “armed attack.” So, can drug activity amount to the use of force?
Traditionally, the concept of use of force has been understood as encompassing physically damaging or injurious actions, as well as indirect uses of force, such as arming and training an insurgent group that, in turn, engages in activities generating that type of harm (Paramilitary Activities, para. 228; Schmitt and Biggerstaff).
Admittedly, drug trafficking undeniably leads to illness and death. However, the causal chain between drug production/shipment/sale and those consequences is attenuated enough to preclude qualification of drug trafficking as a use of force, especially one at the armed attack threshold. After all, the drugs must be distributed and sold, often by individuals or groups that are not members of the drug cartel, and users acting unlawfully have to purchase them. And in most cases, their use does not result in death or serious injury. I do not mean to belittle the horrific consequences of the drug trade; I am simply saying that, as a matter of current international law, qualifying the action as a use of force is very problematic.
There is an interesting contemporary twist to this conclusion. In the cyber context, some States are showing a willingness to treat certain cyber operations that are neither destructive nor injurious as not only uses of force, but even armed attacks. This position has been adopted by such legally sophisticated countries as France, Ireland, Italy, and Singapore (Schmitt and Pakkam, pp. 217-219). Of particular interest is the fact that a number of them have taken the position that a widespread cyber operation targeting the nation’s economy might qualify, even though economic warfare has long been considered not to qualify as a use of force (Schmitt, pp. 905-08). This begs the question of whether the mass shipment of drugs into a State can qualify as a use of force, and thus an armed attack, by this relatively generous understanding.
Such an argument would be hard to make in the current context. First, only a few States have publicly asserted that some non-destructive and non-injurious cyber operation might qualify as an armed attack; most have remained silent. It would thus be premature, at best, to conclude that this argument has attained the status of customary international law (which, given that it is nowhere enshrined in treaty, it would need to do before it may be relied on by a State using force on that basis). Moreover, the causal relationship between a cyber operation and the harm it intentionally causes is direct, and the ensuing consequences typically manifest quickly. The Tallinn Manual experts and numerous States have pointed to these factors, inter alia, as useful in determining when a cyber operation amounts to a use of force (Tallinn Manual 2.0, p. 334; Schmitt and Pakkam, pp. 216-17). Even the United States has emphasized the significance of causal proximity in these assessments. Most cartel drug activity falls short on both counts.
Of course, if foreign drug cartels engage in violent actions against a State at the level of an armed attack, that State would be entitled to respond forcibly in self-defense against them so long as the other conditions on self-defense are satisfied. For instance, crossing into the United States and attacking U.S. law enforcement agents or targeting U.S. military personnel supporting host nation counter-drug operations certainly could amount to an armed attack, so long as the attacks were of the requisite level of severity. It is nevertheless important to recall that not every shot fired at a U.S. law enforcement agent will be considered a use of force, let alone an armed attack, under international law. The United States, like all other nations, has criminal laws that are used to punish offenses like murder and other violent crimes, which is generally the applicable paradigm when organized criminals – as opposed to organized armed groups – are engaging in violent acts.
Other Considerations: When is the Resort to Self-Defense Permissible?
Of course, there are other issues surrounding self-defense that would apply to the resort to defensive force against cartels that use violence or, assuming for the sake of discussion that my position on qualification as an armed attack is wrong, cartel drug-related activity.
A key debate surrounds applicability of the right of self-defense to actions by non-State actors like drug cartels. I have long been of the opinion that there is ample State practice and opinio juris at least since the 9/11 attacks, including on the part of the United States and NATO allies, to support such a right (DoD Law of War Manual, §1.11.5.4; Warsaw Summit Communique).
However, this view is not universally held (see, e.g., Haque; Hakimi), and the ICJ has on two occasions hesitated to endorse it (Armed Activities, para. 146; and Wall, para. 139). By this more traditional understanding, a drug cartel must be acting “by or on behalf” of a State or with its “substantial involvement” (Paramilitary Activities, para. 195) to be the target of forcible defensive action. Based on open-source material, it does not appear that the Venezuelan government is involved in Tren de Aragua activities to this extent (U.S. National Intelligence Council Memorandum), which would preclude the application of self-defense law irrespective of the armed attack question.
And even if forcible measures are permissible in self-defense against non-State actors and drug activities qualify as an armed attack, the response would have to satisfy the conditions of necessity and proportionality (see, e.g., Paramilitary Activities, paras. 194, 237; Nuclear Weapons, para. 41; Oil Platforms, paras. 43, 73-74, 76; DoD Law of War Manual, § 1.11.1.2 and 1.11.1.3). In the context of drug cartel activities, necessity requires that law enforcement or other non-forcible measures, whether by the victim or other States, be insufficient to address the activity to which the self-defense responds. And proportionality would limit the degree of force required in the circumstances to respond to those activities. For instance, it would be unlawful to forcibly seize control of territory from which a cartel operates if forcible maritime operations could effectively block shipment of the drugs from that territory into the State acting in self-defense.
I struggle to see how the September 2 strike would satisfy these conditions, given that the U.S. Navy and Coast Guard have extensive experience in maritime interception. Indeed, Rubio acknowledged that capability in his explanation of the attack’s rationale. His point was that individual intercepts do not solve the broader problem. That argument might answer the necessity issue, but not proportionality, for the same result (blocking the shipment of the drugs aboard the boat that was destroyed) could likely have been accomplished without destructive and lethal force at this level. I hasten to add that I do not have all the facts surrounding the incident, and every assessment is fact-dependent.
Of particular relevance in the counter-drug scenario is the ICJ’s widely accepted conclusion in Paramilitary Activities that qualification as an armed attack depends on the “scale and effects” of the underlying use of force (para. 195). The precise meaning of “scale and effects” remains elusive, but two points bear directly on its application to drug cartel activities.
First, recall that the prevailing view is that an armed attack is the “most grave form” of force (para. 191). Therefore, even if I am wrong and the right applies to drug trafficking, in only the most egregious cases would a cartel’s drug activities rise to the level of an armed attack. The same would hold for isolated, sporadic acts of violence. As explained above, this point would not be an obstacle vis-à-vis the U.S. position that equates the armed attack and use of force thresholds.
Second, individual acts may be aggregated to reach the requisite level of severity (see, e.g., NATO Brussels Summit Communique, para. 32). Thus, assuming solely for the sake of analysis that drug activities, standing alone, can qualify as an armed attack, repeated shipments of drugs by a particular cartel like Tren de Aragua into the United States could be assessed as a whole when evaluating scale and effects. But aggregation of unrelated shipments (for instance, by different drug cartels that are not cooperating) would be inappropriate, as would aggregation of sporadic, unrelated violent acts. This being so, the United States cannot simply assert that there is a “drug crisis” giving it a right of self-defense against drug cartels generally.
As these few points make clear (there are others), even if a State could overcome the hurdle of qualifying drug activity as an armed attack in principle, many other requirements of self-defense would act to limit its options.
When is a right of self-defense needed legally?
International law does not prohibit the use of force in the Article 2(4) sense against individuals or groups having no relation to a State, like an independent drug cartel. It is an interstate prohibition that bars the use of force by one State against another. This begs the question of when assertion of a right of self-defense is even necessary in the first place.
[Note: I am not here assessing the specific strike on the apparently unflagged boat on the high seas. My aim is to assess the broader legal framework for such operations going forward.]
Self-defense is a circumstance precluding the wrongfulness of a State’s otherwise unlawful action, a so-called “internationally wrongful act” in the law of State Responsibility (Articles on State Responsibility, arts. 2 and 21). In the counter-drug context, there are two key cases where self-defense plays this role. As explained, they only apply if the drug cartel concerned is engaged in violence at the armed attack level against the State or if drug activity per se can qualify as an armed attack (a contention I rejected above).
Perhaps most importantly, drug cartels are almost always based in the territory of a State that is not directly involved in the group’s activities. Clearly, a State that is the object of an armed attack by such a group could use force against the group in self-defense with the consent of the territorial State (ASR, art. 20) or Security Council authorization under Chapter VII of the UN Charter. But penetrating another State’s territory to strike a drug cartel without such authority would violate the territorial State’s sovereignty and, especially if I am correct about the self-defense analysis above, it would amount to a prohibited use of force against the territorial State. This begs the question of whether self-defense can serve as a circumstance precluding wrongfulness in order to do so. There are two views.
According to one, another State’s territory may not be penetrated, even in situations of self-defense (see, e.g., the reaction to the 2008 Colombian operations in Ecuador, Ruys, pp. 462-63). In my opinion, the better view is that a State may non-consensually enter the territorial State to conduct forcible defensive measures against non-State actors if the latter State is “unwilling or unable” to put an end to non-State actor activities there (on State support for the approach, see Chachko and Deeks; Schmitt and Pakkam, pp. 226-28).
But this latter approach is subject to substantial limitations, the most significant being that the group’s actions must qualify as an ongoing or imminent armed attack in the first place. And even if that condition were satisfied, if the territorial State is willing and able to engage in effective law enforcement actions against the cartel, the victim State would be estopped from non-consensually entering the territory in self-defense because the necessity criterion highlighted earlier would not be satisfied.
A circumstance precluding wrongfulness would likewise be needed if a State engages in counter-drug operations against a cartel that would violate other rules of international law, most notably human rights law. As noted, I leave the substance of that law to others, but in principle, self-defense would allow some limited use of force against the individuals taking a material part in an activity qualifying as an armed attack, so long as targeting them was necessary to terminate the attack or prevent an imminent one. Of course, the manner in which the operation is carried out would have to comply with any human rights obligations of the State concerned.
Armed Conflict
The second issue that has gained traction in some U.S. circles is whether drug activity can qualify a situation as an “armed conflict” under the law of armed conflict. If so, the law of armed conflict is the primary source of rules governing the operations, including those allowing status-based targeting. I hasten to add that human rights law continues to apply, albeit subject to the principle of lex specialis (DoD Law of War Manual, § 1.6.3.1).
In this regard, it must be cautioned that the existence of an armed conflict does not necessarily render even LOAC-compliant actions lawful. To take the most obvious example, every Russian military operation, including those targeting military objectives and Ukrainian combatants, is a continuing violation of the jus ad bellum. The fact that a conflict is international in character simply means that LOAC rules shape how its operations must be conducted; compliance does not mean the use of force is lawful under other bodies of law.
To be crystal clear, the fact that a State is involved in an armed conflict does not necessarily mean it may lawfully resort to force.
If there is no armed conflict, human rights and other law enforcement-relevant rules are the principal sources of rules and obligations; most LOAC rules are inapplicable. In such circumstances, weapons may not be used “against persons except in self-defence or defence of others against the imminent threat of death or serious injury, to prevent the perpetration of a particularly serious crime involving grave threat to life, to arrest a person presenting such a danger and resisting their authority, or to prevent his or her escape, and only when less extreme means are insufficient to achieve these objectives” (Basic Principles on the Use of Force and Firearms by Law Enforcement Officials; see also U.N. Human Rights Committee, General Comment 36, para 12).
The most likely classification of hostilities between a State and a drug cartel is non-international armed conflict. In a well-accepted definition, the Appeals Chamber of the International Criminal Tribunal for the former Yugoslavia (ICTY) described NIACs as “protracted armed violence between governmental authorities and organized armed groups or between such groups within a State” (Tadić, para. 70; see also ICTR, Akayesu, para. 619; ICC, Bemba, para. 229). From this description, two essential criteria emerge–participation by an organized armed group and a particular level of intensity (DoD Law of War Manual, § 17.1.1).
As to the first requirement, the ICTY has noted that “some degree of organisation by the parties will suffice to establish the existence of an armed conflict. This degree need not be the same as that required for establishing the responsibility of superiors for the acts of their subordinates within the organization, as no determination of individual criminal responsibility is intended under this provision of the Statute” (Limaj, para. 89). Considering the nature of their criminal enterprise, most drug cartels are likely to exhibit a high degree of organization. Whether they count as an organized armed group, as understood by LOAC, is a different matter (Cf. the Fifth Circuit ruling earlier this month that Tren de Aragua was “not the kind of organized force or engaged in the kind of actions necessary to constitute an invasion or predatory incursion” (emphasis added)).
More problematic in the case of drug activity is the intensity criterion. Low-level periodic violence, such as riots and civil disturbances, is insufficiently intense to satisfy the requirement (Army/Marine Corps, Commander’s Handbook on the Law of Land Warfare, para. 1-15); so too would be isolated violent acts, even murder, by a drug cartel. Beyond this limitation, no brightline test exists for assessing the requisite level of violence.
However, in an effort to put flesh on the normative bone, ICTY decisions have cited such factors as “the number, duration and intensity of individual confrontations; the type of weapons and other military equipment used; the number and calibre of munitions fired; the number of persons and type of forces partaking in the fighting; the number of casualties; the extent of material destruction; and the number of civilians fleeing combat zones” (Haradinaj, para. 49). As these indicators suggest, the intensity criterion is about engaging in hostilities at a certain level. It involves the direct application of violence between the State and an organized armed group. It is violence that is akin to direct combat. This is not the type of violence that we see with Tren de Aragua in the United States. Drug activity is unlawful, but it is not “protracted armed violence.”
It is occasionally suggested that drug cartel violence cannot qualify as non-international armed conflict if motivated by purely criminal, rather than political, aims (see, e.g., Sánchez, p. 502-03). I disagree (see also Redaelli and Arévalo, 654-60; Vité, p. 78). As noted by the ICTY, “[the determination of the existence of an armed conflict is based solely on two criteria: the intensity of the conflict and organisation of the parties, the purpose of the armed forces to engage in acts of violence or also achieve some further objective is, therefore, irrelevant” (Limaj, para. 170). Accordingly, I see no obstacle to classifying drug cartel violence against a State as a NIAC, so long as it is at the requisite level of intensity. In my opinion, for instance, a good case can be made that at various times, Colombia and Mexico have been involved in NIACs with certain drug cartels.
Importantly, the State’s actions may trigger a NIAC when one did not previously exist. This did not occur during the Sept. 2 speedboat strike because the attendant hostilities were neither protracted nor at the requisite level of intensity. However, if the United States continues to conduct operations against Tren de Aragua, at some point the requisite threshold will be reached, and LOAC applicable in NIACs will govern U.S. operations.
In some situations, NIACs can be “internationalized,” a possibility that applies to those involving a drug cartel. In its landmark Tadić case, the ICTY’s Appeals Chamber developed an “overall control” test for determining when foreign State involvement transforms a conflict between a State and an organized armed group into an IAC between that State and the State that is supporting the group (para. 146). By this test, internationalization occurs when a State plays “a role in organising, coordinating or planning the military actions of the military group, in addition to financing, training and equipping or providing operational support to that group” (para. 137; see also, e.g., ICC, Lubanga, para. 211; ICTY, Kordic, para. 111; Bosnia and Herzegovina v Serbia and Montenegro, paras. 402-402).
Based on open-source material including declassified U.S. intelligence assessments, it does not appear that the Venezuelan government is involved in Tren de Aragua activities to this extent. And even if a relationship of that level existed, it would still be challenging, under current understandings, to characterize drug smuggling, standing alone, as “hostilities,” the threshold condition precedent to the existence of an IAC.
Concluding Thoughts
The U.S. Navy’s attack on Tren de Aragua’s speedboat, and the broader U.S. policy it appears to represent, underscores the deep tension between the understandable impulse to “wage war” on narcotics organizations that have wreaked havoc inside the United States and the limits of international law. In my view, the right of self-defense did not justify the September 2 strikes (if that right is required to do so), and the United States is not involved in an armed conflict with Tren de Aragua. But I fear that the rhetoric of “narco-terrorism” and the political attractiveness of military responses to transnational crime are outpacing the law.
This reality is highly problematic, not least for the United States. We seem to be on a normative slippery slope that endangers the very values the right to use force in self-defense is meant to protect. This is not to deny the devastating consequences of cartel activity, which is measured in lives lost, communities destabilized, and governance undermined. However, pushing international law’s boundaries to the breaking point risks undermining the coherence of international law and sets precedents that other States are likely to exploit for their own purposes.
