Arsen Ostrovsky 
Arsen Ostrovsky 
Israel’s recent strikes on Iranian terrorist infrastructure have predictably reignited debates about the legality of preemptive self-defense under international law. Let’s dispense with the posturing: these strikes were not only lawful, they were necessary, and there is nothing controversial about what happened — legally, morally, or strategically.
The concept of preemptive self-defense has long occupied a contested space in legal scholarship. Article 51 of the UN Charter affirms that:
Critics argue that this language imposes a strict temporal requirement: self-defense can only begin after an armed attack has already occurred. But this interpretation has always been tenuous — and increasingly divorced from operational realities. The law is not meant to incentivize victimhood, which is why many scholars, more rooted in reality, point out that waiting for a missile to land before acting is not international law — it’s international suicide.
That debate, however, is irrelevant here. Because Israel’s right to self-defense is not merely being invoked preemptively.
For decades Iran has openly vowed to destroy the State of Israel, and they have taken many steps to assure the world that they actually mean it. Since October 7, Iran and its proxy forces — Hezbollah in Lebanon, the Houthis in Yemen, and militias in Syria and Iraq — have launched thousands of missiles and rockets at Israeli population centers. Each launch was not merely a political provocation, but a war crime: a direct attack on civilians. Under any reading of Article 51, these constitute armed attacks in the strictest legal sense.
And that brings us to the next question: Once the right to self-defense has been triggered, what exactly are its limits?
Customary international law, particularly as articulated in the Caroline doctrine, imposes two key conditions: necessity and proportionality. As Professor Amos Shapira has explained, the central issue is “the dimensions of the risk created by the adversary and the means reasonably necessary to repel, or remove, that risk.” Likewise, Hans Kelsen rightly warned that a right to self-defense that does not allow for the neutralization of the underlying threat is no right at all.
Israel’s response to persistent attacks falls squarely within this framework. The threat is not hypothetical. It is ongoing, declared, and demonstrated. Iran has openly vowed to destroy the State of Israel. Its proxies act constantly to make good on that promise. In recent days Iran has enriched enough uranium to build 15 nuclear bombs. The existential threat is, as the law requires, “instant, overwhelming, leaving no choice of means, and no moment for deliberation.”
In that context, Israel’s latest actions were proportionate and disciplined. Legally, Israel would have been justified in going much further. But it chose targeted, calibrated strikes instead — demonstrating not only military precision, but also strategic restraint.
Some commentators will nonetheless characterize these operations as escalatory or destabilizing. But that critique inverts the causality. The destabilization began with Iranian aggression. Israel’s actions are a stabilizing response — aimed at restoring deterrence and preventing further loss of life.
History has made one lesson painfully clear: peace is not the product of goodwill gestures or international declarations. It is secured by credible deterrence. The idea of peace through strength — long dismissed by the willfully naive — has never been more relevant. Israel’s recent actions embody this principle. When faced with an implacable adversary whose stated goal is your annihilation, strength is not a provocation; it’s a prerequisite for survival. And demonstrating that strength, responsibly and with restraint, is not just a legal right — it is a moral obligation to one’s citizens and allies.
To be clear, deterrence only works if it is believable. That is why the Israeli response was not just defensive—it was declarative. It sent a message not only to Tehran, but to every state and non-state actor watching: We are not passive targets. We will not wait quietly for missiles to rain down or for uranium to be weaponized. We will act, decisively and proportionately, to protect our people. That is how peace is preserved — not by appeasement, but by the unmistakable resolve to uphold red lines and enforce consequences.
There are only two sides in this war: Those who want to kill millions of innocent people, and those who do not. Each person must choose who they want to stand with. But regardless, the international legal system recognizes the right of states to defend themselves. That right is not a theoretical construct, nor is it a suicide pact. It exists for precisely moments like this one.
If the international community is genuinely committed to law and order, then Israel’s actions should not just be understood. They should be affirmed. In addition, Iranian leaders and regime-aligned institutions have repeatedly issued statements calling for the destruction or downfall of both America and Europe. If anything, the world should say thank you.
The article was written together with John Spencer is chair of urban warfare studies at the Modern War Institute (MWI) at West Point and host of the ”Urban Warfare Project Podcast.” He is the co-author of ”Understanding Urban Warfare” and Mark Goldfeder that he is Director of the National Jewish Advocacy Center and a law professor at Touro University.
Published in Daily Wire, June 14, 2025.