This fear wasn’t because of America’s long-standing prohibition of “assassination,” forged during the Cold War to check the excesses of the CIA. Successive administrations since September 11 have interpreted this ban narrowly, arguing that singling out an individual for death on the battlefield doesn’t really count. The ban arose in response to covert CIA plots to, for example, kill Fidel Castro with an exploding cigar during peacetime—essentially, attempting to kill because of political differences, not in wartime self-defense, said Matthew Waxman, who directs the National Security Law Program at Columbia University and served in the Bush administration. The Obama administration used the term targeted killing for strikes on terrorist leaders in overseas battlefields—arguing that they fell under a right to self-defense in an ongoing war against al-Qaeda.

Not everyone is convinced. “These killings cannot be distinguished from unlawful assassination,” Mary Ellen O’Connell, a professor at Notre Dame Law School, told me.

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The Soleimani killing would be no more or less legal in this context than that of a nonstate leader just because he worked as a top general, in uniform, for a state. If you subscribe to the idea that targeting an individual combatant in self-defense isn’t the same as an assassination, then Soleimani is fair game—provided you credit Trump’s claim that Soleimani was plotting “imminent and sinister” attacks against Americans. A State Department official on a phone call with reporters noted, “Assassinations are not allowed under law.” But the official argued that this wasn’t one. “The criteria is: Do you have overwhelming evidence that somebody is going to launch a military or terrorist attack against you? Check that box. The second one is: Do you have some legal means to, like, have this guy arrested by the Belgian authorities or something? Check that box, because there’s no way anybody was going to stop Qassem Soleimani in the places he was running around—Damascus, Beirut. And so you take lethal action against him.”

If you believe targeted killings is a sanitized term for assassinations, which have become normalized in the drone-war era but are no less illegal, then targeting Soleimani is a war crime, especially since there’s no formal state of war between the United States and Iran. “Preemptive self-defense is never a legal justification for assassination,” O’Connell said. “Nothing is. The relevant law is the United Nations Charter, which defines self-defense as a right to respond to an actual and significant armed attack.”

Two administrations sidestepped this debate when it came to Soleimani, not as much for legal or moral reasons as for strategic ones. The two sides of this conflict have opted for other forms of confrontation, from proxy fights to sabotage to cyberattacks to sanctions, but they didn’t kill each other’s generals. Now that barrier has been shattered, leaving the world to await Iran’s next move in a game with suddenly higher stakes. From the Iranian perspective, it doesn’t much matter whether the U.S. administration considers Soleimani’s death an assassination or not. He’s still a dead general.