On Tuesday, President Donald Trump announced that the U.S. military had killed six people in a strike on a boat that, Trump said, was “trafficking narcotics.” It was the fifth such strike in international waters since Sept. 2, with a combined death toll of 27 people. The Trump administration has promised even more to come, but we already know enough about these strikes to call them what they are: extrajudicial killings that are flagrantly illegal under both domestic and international law. No one is under any illusions that anyone in the administration is likely to listen to the voices across the political spectrum who agree with this conclusion: Vice President (and Yale Law graduate) JD Vance declared he doesn’t “give a s---” whether the strikes are illegal. But it is critical that the rest of us refuse to treat these strikes as a new normal. Everyone who cares about the rule of law and human rights must continue to press for transparency, accountability and an immediate end to this illegal and lethal campaign. Whatever the government now says in an attempt to cover its tracks does not magically unlock legal authority to use force.For weeks, the administration has trumpeted these strikes with grainy videos of explosions and unsupported allegations that the people killed are drug cartel members and “terrorists” (neither of which would justify extrajudicial killings). But underneath the White House’s bravado, The Wall Street Journal reported in mid-September that “some military lawyers and other Defense Department officials are raising concerns about the legal implications,” including for potential violations of the federal criminal murder statute. And they are right to worry, because all indications are that these strikes have violated the federal criminal murder statute as well as the prohibition on murder in the Uniform Code of Military Justice, with few plausible defenses in sight.Subsequently, the administration informed Congress that Trump unilaterally “determined” that the United States is in a noninternational armed conflict against certain gangs and cartels that it has (again unilaterally) designated as terrorist organizations. This was a transparent attempt to “legally backfill their operations,” Brian Finucane, a former State Department lawyer and expert in the laws of war, told The New York Times. And while CNN reports that the Office of Legal Counsel has produced a secret memo (which has not even been shown to Congress) that authorizes lethal strikes “against a secret and expansive list of cartels and suspected drug traffickers,” it’s not clear whether that legal opinion was issued before the U.S. started killing people at sea. The government’s apparent position is that drug cartels are engaged in an “armed attack” on the United States because (as The New York Times reported) “100,000 Americans die annually from [drug] overdoses.” Tragic as that is, drug cartels are criminal groups — and that’s in fact how our many drug laws deal with them and how the government has treated such groups throughout our history. Moreover, these strikes were conducted thousands of miles from American shores, and there does not seem to be any evidence that the boats targeted were even heading to the United States. In fact, Secretary of State Rubio said after the first lethal strike that the boat’s contents were “probably headed to Trinidad or some other country in the Caribbean.” In one case, the boat had literally turned around before it was bombed. In another, Colombian President Gustavo Petro alleged that the boat targeted was actually Colombian, with Colombian citizens on board. The Trump administration disputed that claim, but a new CNN report indicates that Colombians were deliberately targeted.In fact, whatever the government now says in an attempt to cover its tracks does not magically unlock legal authority to use force, and the boat strikes cannot be justified — full stop. There is no credible factual or legal argument that the United States is engaged in an armed conflict with any drug cartel under international law. Under international law, an armed conflict between a nation and a nonstate group — the kind of noninternational armed conflict the president is now claiming exists — requires “protracted armed violence between governmental authorities and organized armed groups or between such groups within a State.” Even if the law of war were to apply (and it absolutely does not), it would prohibit direct attacks against civilians who are not directly participating in the conflict.Drug smuggling has undoubtedly harmful consequences and costs, but it is not even arguably “armed violence,” let alone the kind of sustained violent clashes that meets the criteria for an armed conflict. And there is no evidence that the groups allegedly targeted in these boat strikes are sufficiently organized and conducting military hostilities and operations against the United States, either.Notably, the president has not asked Congress for any authorization for use of force or declaration of war. My organization, the ACLU, does not take positions on the political merits of U.S. conflicts abroad, but we have long insisted—from the Vietnam War to the bombing of Cambodia to the post-9/11 era—that the Constitution assigns only to Congress the power to authorize use of force. More from MSNBC DailyMust reads from Today's listJust as the president announcing an armed conflict does not make it so, Congress similarly cannot convert a deliberate series of criminal attacks into a lawful use of force. And whatever the identities of the 27 people the U.S. government has killed in these strikes, they are civilians under both international and domestic law. The murder statutes in both U.S. criminal and military law prohibit the use of lethal force against civilians, and no plausible exception applies here. Even if the law of war were to apply (and it absolutely does not), it would prohibit direct attacks against civilians who are not directly participating in the conflict — and that includes a drug cartel’s criminal activities do not clear the bar. The Trump administration’s astonishing assertion of authority to use lethal force would be laughed out of any courtroom anywhere — were its consequences not so absolutely serious.Congress, the courts and the American people must bring an end to the executive branch’s ever-more-capacious and unilateral expansions of authority to use lethal force abroad. Over the past 25 years, administrations of both parties have pushed aggressive theories of executive power by expansively interpreting the executive branch’s Article II and statutory powers. In areas of foreign affairs and national security in particular, the courts have for too long excessively deferred to the office of the president. The institutions with the power to check these activities should step up to actually do so. A decades-long one-way ratchet of executive power helped produce Trump’s latest legally and morally abominable acts, and these strikes should be a wake-up call to all.Brett Max KaufmanBrett Max Kaufman is senior counsel in the ACLU’s Center for Democracy.