Non-starter.

While we can point to cases where the prohibition on war has not been observed — and the United States has been both one of the greatest defenders and one of the greatest offenders in the last several decades — it’s a mistake to suggest that the legal principles are meaningless or ineffective. The modern legal order is grounded in the prohibition on war, even if it is not always perfectly observed.

I said earlier that the test of a legal principle is not just whether it is violated, but what response meets that violation. And here we have seen a response much more robust than many expected when this war began. Normally moribund international legal institutions have suddenly sprung to life in response to the illegal invasion. Here, I will detail international community responses of four kinds: condemnation, outcasting, arming, and accountability.

First, international law and international institutions have been used to condemn Russia’s illegal war. As the invasion began, the U.N. Security Council tried to pass a resolution deploring the Russian invasion and demanding the withdrawal of Russian forces from Ukraine, but Russia vetoed it. Although Russia was able to exercise its veto power on the Security Council to prevent it from mandating any punitive action, the country’s almost complete isolation within the organization was swift and thorough. Soon after Russia blocked the resolution, the Security Council activated the long-dormant Uniting for Peace Resolution. That resolution, which was first adopted in 1950, provides that if the Security Council, due to lack of unanimity among the permanent members, fails to exercise its responsibility to maintain international peace and security, the General Assembly will consider the matter immediately with the view to making recommendations to members.

When Russia vetoed Security Council action, the Uniting for Peace Resolution was used to refer the matter to the General Assembly, which voted overwhelmingly to demand that Russia “immediately, completely and unconditionally withdraw all of its military forces from the territory of Ukraine within its internationally recognized borders.” Only a small handful of states — Belarus, Eritrea, North Korea, and Syria — voted with Russia against the resolution. The other countries that Russia might have hoped would support it, most notably China, chose instead to abstain. That majority was sustained through several additional votes, the latest coming only hours before the conflict entered its second year, with 141 states voting to condemn the war and demand that Russia “immediately, completely and unconditionally” withdraw all of its military forces from the territory of Ukraine, and just seven, including Russia, voting against.

The International Court of Justice (ICJ) also has played a role in condemning the Russian invasion. On February 26, just two days after the invasion began, Ukraine submitted an application to the ICJ, beginning proceedings against Russia. The application took Putin’s outrageous and baseless claims that Ukraine was committing genocide in its eastern regions and turns them against him. Russia, as a party to the Genocide Convention, has agreed that the ICJ is the forum at which disputed allegations of genocide may be resolved. In a brilliant act of lawyering, Ukraine seized on this fact and argued that Putin’s claims provide the ICJ grounds for jurisdiction to adjudicate whether, indeed, any such genocide has occurred. The ICJ immediately scheduled a hearing on the matter for March 7. The ICJ then found against Russia, ordering Russia to cease the war immediately.

Second, international law has been used to “outcast” Russia. Here I use the term outcasting in a specific manner. Drawing on my work with Shapiro, I mean the mechanism for enforcing international law where states exclude the law-violating state, here Russia, from the benefits of international cooperation to which it would otherwise be entitled. Russia has been excluded from a number of international organizations, including the Council of Europe. But the main form of outcasting faced by Russia since the war began has been a system of unprecedented economic sanctions that is one of the most expansive the world has seen outside of Security Council-ordered sanctions. I will say more in a moment about whether those sanctions have been effective, but for now, the key point is that the sanctions response has been significant and widespread.

Third, the condemnation and outcasting of Russia have been accompanied by another important development — the arming of Ukraine. The United States alone has provided over $70 billion in aid to Ukraine, including $44 billion in military aid. The role of law here is less obvious, but it is very much present. Law has a legitimizing value — the states supporting Ukraine are acting in support of a state that is legally in the right. That has been an important part of the political debate in a number of key countries, particularly Germany, but it is important to the willingness of states globally to support Ukraine against Russia’s attempt at illegal conquest. It is, moreover, important that it is perfectly legal to provide arms and other support to a state that is defending itself against an illegal war and that is abiding by international humanitarian law in the process. By contrast, it is illegal to support a state that, like Russia, is waging an illegal war — as doing so is to aid and assist that state in its internationally wrongful acts.

Fourth, the illegal war has been and will be subject to criminal prosecution and other legal accountability. On February 28, just four days after the invasion began, International Criminal Court (ICC) Prosecutor Karim Khan announced that he was seeking authorization to open an investigation as soon as possible. Neither Russia nor Ukraine is a party to the Rome Statute, which created the ICC and gives it jurisdiction. But in 2013, Ukraine legally accepted the court’s jurisdiction over alleged crimes occurring on its territory. On March 2, Khan announced that he had received 39 state referrals and that he would immediately proceed with an investigation. Never had the ICC responded so quickly to the outbreak of a conflict.

That investigation has recently resulted in the indictment of both Putin and Maria Alekseyevna Lvova-Belova, currently the presidential commissioner for children’s rights in the Russian Federation. This is an extraordinary step for international criminal justice.

In addition to criminal accountability, the U.N. General Assembly has also endorsed the creation of a reparations mechanism, and there is a significant effort right now to think about how to compensate Ukraine for the damage done by Russia in the course of the war.

All of this response suggests that there have been real consequences for Russia in its violation of the prohibition on war. And while that response has not been sufficient to bring an end to the war, it has sent a clear message that the violation of the prohibition on war remains core to the international system. That message is directed not only at Russia. It is intended, too, for any state considering following in Russia’s footsteps in the future. I think it is safe to say that the robust response will give states considering a similar invasion in the future reason to reconsider.

In short, the response to an illegal war launched by a nuclear-armed state with a veto on the Security Council has been far more effective than anyone had reason to hope at the outset.