Is Russia's invasion of Ukraine justified?

Whether Russia's invasion of Ukraine is justified is a central point of global debate, dividing Russia and its supporters from Ukraine, international legal bodies, and the vast majority of the global community.

Russia has defended its military actions using national security, humanitarian, and historical arguments. Conversely, Ukraine and most of the international community strongly reject these claims, viewing the invasion as an illegal and unprovoked war of aggression.

Arguments Presented by Russia (and Supporters)

The Russian government and some foreign policy analysts (particularly those belonging to the "realist" school of international relations) have put forward several arguments to justify the military operation:

The Kremlin argues that the eastward expansion of the North Atlantic Treaty Organization (NATO) since the end of the Cold War poses an existential threat to Russian security. Russia contends that a potentially NATO-aligned Ukraine on its border crosses a "red line" and would allow Western military infrastructure to threaten Russian territory. Some prominent realist political scientists, such as John Mearsheimer, have argued that the West’s long-term policy of trying to integrate Ukraine into Western security structures directly provoked Russia’s security anxieties.

Russia claimed it initiated its "special military operation" in part to defend the Russian-speaking populations of the Donbas region (Luhansk and Donetsk). Moscow alleged that the Ukrainian government was engaged in systematic persecution and "genocide" against these populations. Russia officially recognized the independence of the Donetsk and Luhansk People's Republics, arguing that under Article 51 of the UN Charter, it had the right to engage in "collective self-defense" on their behalf.

President Vladimir Putin has repeatedly asserted that Russians and Ukrainians are "one people" who share a deep historical, spiritual, and cultural heritage. From Moscow’s perspective, the post-Soviet borders established in 1991 artificially separated historically Russian lands, and Ukraine’s integration into the Western sphere of influence is seen as an attempt to weaken Russia.

Russia has claimed its military actions are aimed at neutralizing Ukraine's military capabilities and removing far-right, ultranationalist elements within the Ukrainian government and armed forces, which Moscow characterizes as "neo-Nazi" and inherently hostile to Russia.

Arguments and Evidence Presented by Ukraine and the International Community

Ukraine, its allies, and the overwhelming majority of international organizations and legal scholars reject Russia's justifications, arguing they have no basis in reality or international law:

The legal consensus among international scholars and the United Nations is that Russia's invasion violates Article 2(4) of the UN Charter, which prohibits the threat or use of force against the territorial integrity or political independence of any state. On March 2, 2022, the UN General Assembly adopted Resolution ES-11/1, which "deplored in the strongest terms the aggression by the Russian Federation against Ukraine". The resolution passed with an overwhelming majority of 141 states in favor, 5 against (Russia, Belarus, Syria, North Korea, and Eritrea), and 35 abstentions.

The International Court of Justice (ICJ) and independent human rights monitors have found no evidence supporting Russia's allegations of "genocide" against Russian-speakers in eastern Ukraine. In March 2022, the ICJ ordered Russia to immediately suspend its military operations, ruling that Russia had no legal basis to use force under the pretext of preventing genocide. Furthermore, legal experts state that Article 51 of the UN Charter applies only in response to an active or imminent "armed attack," which Ukraine had not launched or threatened against Russia.

Under international law, Ukraine is a fully sovereign and independent nation whose borders were explicitly recognized by Russia in the 1991 Belovezha Accords and the 1994 Budapest Memorandum. As a sovereign state, Ukraine has the inherent right to determine its own foreign policy, democratic governance, and international alliances—including seeking membership in the European Union or NATO—without foreign veto power.

Critics of Russia's narrative point out that Ukraine was not on the verge of joining NATO in 2022, as multiple NATO member states openly opposed its accession. Additionally, analysts argue that if Russia’s primary concern was NATO proximity, its reaction to Finland and Sweden joining the alliance in 2022—which Putin stated did not pose a "direct threat" to Russia—undermines the argument that NATO expansion necessitated a preemptive war in Ukraine.

Many historians, political scientists, and global leaders argue that Russia’s stated pretexts of "de-Nazification" and "defense" are cover for imperialist ambitions. They point to Russia's formal annexation of Ukrainian territories (Crimea in 2014, and Donetsk, Luhansk, Zaporizhzhia, and Kherson in 2022) as evidence that the war is a land grab aimed at erasing Ukrainian national identity and re-establishing a Russian sphere of influence over former Soviet territories.