John Mearsheimer is one of the world’s most influential international-relations scholars and a leading exponent of offensive realism. His analysis of Russia, NATO and Ukraine has shaped international debate for more than a decade, yet several important assumptions and predictions surrounding Russia’s 2022 invasion proved significantly misaligned with events.
This case study does not dismiss realism or Mearsheimer’s contribution to strategic thought. Instead, it examines how deep expertise and a powerful theoretical framework can themselves become analytical vulnerabilities when evidence is consistently interpreted through an established model. Using the Ukraine conflict, the paper explores model lock-in, anchoring, rational-actor assumptions, authority bias, underestimation of Ukrainian agency and the difficulty established experts face in revising long-held positions. The case provides wider lessons for intelligence organisations seeking to develop analysts capable not only of constructing convincing assessments, but of recognising when their own analytical framework may be wrong.
