John Mearsheimer: The Hidden Truth Behind Russia’s Invasion and the Failure of NATO | Ukraine War

Summary

John Mearsheimer argued that the United States and its NATO allies bear the greatest responsibility for the crisis that led to Russia’s invasion of Ukraine. He explicitly acknowledged that Vladimir Putin launched the invasion and is responsible for Russia’s actions in the war, but said Western policy helped create the conditions for it. In his account, Washington pursued a strategy of bringing Ukraine into Western institutions, encouraging it to become a pro-Western democracy, and ultimately admitting it to NATO—moves Russian leaders viewed as an existential security threat.

Mearsheimer disputed the widely held view that Putin invaded to conquer Ukraine and rebuild a Russian empire. He said Putin’s public statements did not establish such an intention and argued that Russia’s initial force of roughly 190,000 troops was insufficient to conquer and occupy a country of Ukraine’s size. He also maintained that Moscow understood the likely costs of occupying a strongly nationalist country. He interpreted Putin’s stated concern instead as preventing Ukraine from becoming a Western military foothold on Russia’s border.

He traced the conflict’s roots to NATO’s 2008 Bucharest declaration that Ukraine and Georgia would eventually join the alliance. Mearsheimer cited warnings from then-U.S. ambassador William Burns and opposition from French President Nicolas Sarkozy and German Chancellor Angela Merkel, who he said understood that NATO membership for Ukraine could provoke Russia. He argued that Western policy continued after 2014: NATO countries trained Ukrainian forces, supplied weapons, held joint exercises, and deepened political ties. He said these steps helped turn Ukraine into a de facto NATO partner and contributed to Russia’s growing alarm in 2021.

Mearsheimer described the war as a catastrophe for Ukraine, citing deaths and injuries, millions of refugees and displaced people, extensive damage to cities and infrastructure, and a severe economic contraction. He was pessimistic about a near-term settlement. In his view, Russia would require Ukrainian neutrality, while the Biden administration and Ukrainian nationalists would reject a settlement that could be presented as a Russian victory.

He also warned that the conflict could widen. If Russia faced major defeat, it might resort to nuclear weapons; if Ukraine faced defeat, the United States or NATO countries could become more directly involved. He cautioned that Western military success could therefore increase the danger of nuclear escalation.

In the discussion, Mearsheimer defended the use of broad international-relations theories, especially realism, while acknowledging that such theories simplify reality and cannot account for every case. He said regional expertise and domestic politics matter, but argued they should be considered alongside the wider balance of power.

Several participants challenged his interpretation. They questioned whether Putin’s statements about Russian-Ukrainian unity, “denazification,” and Soviet history suggested imperial ambitions; whether fear of democracy and “color revolutions” was a more important motive; and whether his account gave enough weight to Russian domestic politics, decision-making, and alternative explanations. Others pressed him on the evidence behind his claims and on why Russia did not respond similarly to NATO ties with Georgia or Finland.

Mearsheimer replied that the evidence available to him supported his interpretation, but said he could be wrong and would revise his view if stronger evidence emerged. He also argued that the invasion may have expanded Putin’s objectives, making a viable, independent Ukraine harder to restore.

Mearsheimer concluded that the 2008 NATO decision was a grave Western policy error and predicted that history would hold the United States and its allies primarily responsible for helping bring about the disaster. The discussion also highlighted a more general disagreement: whether the war is best explained by great-power security competition, Russian imperial aims, fear of democracy, or a combination of these factors.

Presenters and Contributors

• John J. Mearsheimer — speaker
• Stephanie — moderator and questioner; surname not given
• Eric Jones — academic host and questioner
• Nicolas Guillot — introduced Mearsheimer
• Sarah, Jeff, Veronica Angel, Makoto, and Robert Cooper — questioners or contributors
• Other unnamed audience members — participated in the Q&A