Had Ukraine kept nuclear weapons, its relations with the United States, Europe, and organizations such as the European Union and NATO would most likely not have developed as they have over the past 25 years, and Kyiv would have had a huge problem with Moscow—but the underlying facts of the case would have looked different. Consequently, Ukrainians understandably now look back and question the wisdom of giving up nuclear arms. Would Russia have acted as it did in 2014 and 2022 had Ukraine kept some of its nuclear warheads? Russia’s betrayal of its security commitments to Ukraine—not to mention the brutality of the war that the Russian military has waged—will almost certainly make Kyiv leery of any future agreement with Moscow.

Meanwhile, consistent with what US officials had told their Ukrainian counterparts at the time of negotiating the security assurances, Washington has provided significant military assistance to Ukraine, including anti-armor missiles, armored vehicles, heavy artillery, and large amounts of ammunition—an assistance package worth more than $4.5 billion since January 2021 alone. In addition, in May 2022, the US Congress passed another multi-billion-dollar package of military aid and economic support for Kyiv. The United States has also worked with the European Union and other states to impose major economic sanctions on Russia.

The war is a tragedy for Ukraine, which has suffered the deaths of thousands of soldiers and civilians and immense physical damage. But it is arguably also a disaster for Russia, which has lost many more thousands of soldiers, will suffer great economic pain as a result of Western sanctions, and faces a rejuvenated—and very likely soon to enlarge—NATO.