To the extent anyone cares about, you know, legality and stuff:
https://www.justsecurity.org/67970/lawf ... ional-law/
"Gen. Hamid Sarkheili of the Iranian Revolutionary Guard told a crowd of Soleimani mourners on Monday that, “[w]e are ready to take a fierce revenge against America…American troops in the Persian Gulf and in Iraq and Syria are within our reach.” And as if to punctuate their motivation, the Iranian missile attack was accompanied by this familiar refrain of “fierce revenge.”
Iran may think it is justified in what it calls revenge, but its actions and rhetoric are fundamentally inconsistent with international law, ironically the very law Iran invoked to condemn the U.S. attack. Revenge (often called retaliation) is not a lawful basis for a State’s use of armed force. Instead, international law permits a State to use force against another State (or in the view of many, including the United States, non-state organized armed groups)
only when necessary to defend against an imminent, actual, or ongoing unlawful armed attack, or pursuant to a United Nations Security Council resolution. Neither of these bases justify revenge, retaliation, or reprisal; and neither seemed to justify Iran’s threats or attack. Indeed, despite the rhetoric Iran appears to actually understand this, which likely explains why following the missile attack Iran’s Foreign Minister posted on Twitter that the country “took & concluded proportionate measures in self-defense” (contradicting nearly a week of threats of revenge).
Invoking the rhetoric of self-defense does not ipso facto justify a State’s use of military force absent a reasonable basis to conclude the State faced one of the triggering justifications for such necessary self-help action. This applies equally to the United States and Iran, both of which have now launched attacks that could easily be viewed as acts of retribution. Accordingly, if Iran did what it actually promised – launch a military attack to retaliate for the U.S. Soleimani strike and not based on an imminent threat of armed attack by the U.S. — Iran has, paradoxically, engaged in the same illegality it has been condemning.
Self-defense on the international level, like self-defense in any other context, is a legal justification that requires the use of force to be absolutely necessary to protect against an imminent threat of unlawful violence. If that act of violence is completed, this self-help justification expires, unless the victim reasonably perceives an ongoing threat. This “timeliness” aspect of self-defense necessity functions to prohibit a victim of unlawful violence from transforming a genuine self-protection justification into a justification to take revenge.
That is, a U.S attack purely in retribution for earlier Iranian attacks is squarely prohibited by international law, specifically the United Nations Charter. Like an act of self-defense in the individual context, in which responses to and retribution for past violent acts is ceded to the criminal justice system, international law cedes legal authority for enforcement of international law – including violent punishment of aggressors – to the U.N. Security Council. Though greatly embryonic compared to domestic law enforcement systems, and often hobbled by the impact of the veto power vested in the five permanent members of the Security Council (including the United States), this international legal structure with all its limits and flaws remains the primary (if not exclusive) means by which a State responsible for a completed act of unlawful aggression is subjected to sanction."
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"This is why we believe it is so essential that the U.S. administration articulate to the American people and the broader international community a compelling case that it made a reasonable and credible assessment that its Soleimani attack was necessary to prevent another unlawful attack on U.S. military personnel or U.S. facilities – and that such projected attack was imminent, leaving no reasonable time for non-forceful measures to obviate such threat.
It is also why it is per se illegal for Iran to threaten the use of military force to take revenge, even if they pretend to demonstrate respect for international law by emphasizing they will only attack U.S. military targets in a “proportional” way. And it is why Iran and the United States should be forthcoming with the information that led to their respective asserted determinations that their attacks were necessary to prevent subsequent imminent uses of force by their antagonist.
In contrast to Iran’s near-constant refrain of revenge as its basis for a threatened strike – despite claiming that Tuesday’s attack was lawful self-defense – on the other side of the world the Trump Administration has been consistently claiming its strike last week was indeed internationally lawful as an exercise of the inherent right of self-defense. The U.S. immediately invoked the inherent right of self-defense as the principal U.S. legal authority to justify its drone strike in Iraq targeting General Soleimani. The United States attacked the general because, per the State Department, he was planning “imminent attacks against American personnel and facilities in Lebanon, Iraq, Syria and beyond.” Secretary of State Pompeo explained that Americans “are safer in the region” after the U.S. drone strike, because Soleimani’s anticipated actions involved an “imminent attack” that “would have put hundreds of lives at risk.” The Chairman of the Joint Chiefs of Staff, General Milley, affirmed that the U.S. had “the intelligence I saw– that was compelling, it was imminent, and it was very, very clear in scale, scope..” And President Trump claimed the morning after the strike that, “[w]e took action last night to stop a war, we did not take action to start a war,” and he too called the Soleimani’s threat of an attack “imminent.”
The stakes involved in the U.S. military strike and the escalation we now know it generated implicate a wide array of diplomatic, political, and strategic considerations. It is therefore logical and appropriate to scrutinize the U.S. claim of self-defense justification, something that began almost as soon as the attack was executed. And the Iranian missile strike of Tuesday evening should be subjected to the same scrutiny."