Article IV of the 1948 Convention on the Prevention and Punishment of the Crime of Genocide, adopted by the General Assembly of the United Nations, declared, “Persons committing genocide or any other [related] acts… shall be punished, whether they are constitutionally responsible rulers, public officials or private individuals.” Given the present mass atrocities in Ukraine as a result of indiscriminate Russian bombing and missile attacks, we are once more reminded of the agreement made by Vladimir Putin and Xi Jinping at the opening of the recently convened Winter Olympic Games in China: there are “no limits” and there is nothing “forbidden” in their fundamental unity—a unity committed to altering the structure of world power. What is “forbidden” has been a recurring pattern in Ukraine.

In recent days the US ambassador to the United Nations has depicted Russia’s attacks in Ukraine as war crimes. These charges follow on the heels of what NATO Secretary-General Jens Stoltenberg described as a war crime by Russia’s alleged use of cluster bombs. US Congresswoman Victoria Spartz (R-IN), the lone Ukrainian-American member of Congress whose 95-year-old grandmother still lives in Ukraine, publicly protested, “This is not war. This is genocide of the Ukrainian people.” Similarly, the former chief of the economic section of the US embassy in Ukraine has expressed “anger” and “shame” insofar as “the US could do much more to stop this indiscriminate slaughter.” Indeed we could.

Similar questions, though forgotten, were raised in 2014 in eastern Ukraine and in Crimea. Putin’s aim is not in doubt: to reverse the effects of the Cold War, to re-subjugate former East-bloc nations that are now independent, and as his joint announcement with Xi made clear, to re-assert Soviet-style world domination. As it applies to Ukraine, Putin’s method is murder, mass disinformation, and destabilizing mayhem. Simply stated, Russian victory will mean the end of freedom for Ukrainians and an altered configuration of Eastern Europe.

Defining war crimes, of course, is a less difficult task than prosecuting them. Human rights are grounded in the universal and inherent dignity of the human person. Based on international human rights declarations and international law that followed the Second World War, crimes of war entail not only the matter of justice but also the fundamental issue of human dignity and humaneness. Such crimes are to be understood against the backdrop of principles that inhere in the just war tradition—just cause, right intent, legitimate authority, military necessity, discrimination, and proportionality. Putin, alas, has no just cause; his aims are grotesquely perverted and wrongly intended; his authority is totalitarian and despotic; his means of subjugating the Ukrainian people have been devilishly indiscriminate and disproportionate. In short, what we are witnessing are crimes of war.

Measuring war crimes can also be done negatively in light of Putin’s dishonest and patently false claims of “peacekeeping” in Ukraine. “Peacekeeping” does not bomb civilian targets indiscriminately. It does not employ overwhelming offensive force; it is defensive in nature. It does not lay siege to cities. It does not injure or undermine the victim state. It does not result in massive or widespread displacement of the civilian population. And its true aim is to help secure a lasting peace. By all measurements, Putin is committing war crimes.

Prosecuting such crimes, however, encounters serious hurdles for the international community, not the least of which are the establishment of a threshold of evil, the collection of evidence of that evil by a competent authority, the time needed to adjudicate over and punish such evil, and of course, the moral backbone to do what is right and just. The International Criminal Court was created to deal with the “severest” cases—mass atrocities such as those that befell Rwanda, former Yugoslavia, and Cambodia. At present, Russia’s power and use of propaganda prevent any sort of reckoning.

The US and NATO nations, though unified, balk before the matter of risk—risk of war’s escalation, risk of nuclear attack, risk of violating supposed “neutrality” and non-intervention policy, and the risk of recrimination due to arms shipments that Moscow has described as “legitimate targets.” However, coalition nations may not excuse themselves on the basis of these purported risks. Our continual excuse-making for what we will not do—we will not engage militarily, we will not enforce a no-fly zone, we will not consider “red-line” strategies—only emboldens Putin.

Behind every Russian threat is lodged falsehood, intimidation, and manipulation. Every decision on our part—to act or not to act—entails risk. The question is what we will do, whether we are willing to deter Putin, and whether that risk is moral and humane or a failure of nerve. The greater risk is to permit Russian victory in Ukraine, thereby guaranteeing not only the end of freedom for the Ukrainian people but an opening of the door to the re-subjugation of other peoples in the wider region. Putin has ignored the Budapest Memorandum of 1994, signed by the United States, the United Kingdom, Russia, and Ukraine, which guaranteed the territorial integrity of Ukraine. We have ignored it as well. The US and NATO nations are thus faced with an immediate question: Do the Ukrainian people have a sovereign right to exist, and therefore, should Russia’s impunity be tolerated? At bottom, do we have the moral backbone to deter Putin? Which, of course, raises the question of whether Putin should be prosecuted as a war criminal.

The West’s weakness, as mirrored in its half-measures in the war, needs to be called out. Ukraine stands in need of Western nations engaging Russia from a position of strength and deterrence. We stand at a moment of truth for all of the world, and particularly, the Western world. Will we allow Russia to intimidate, bomb, and terrorize Ukrainians into a final—and irreversible—submission and subjugation?

Shame on us if we do not act to deter what amount to escalating war crimes.