“When you're a country like Ukraine and you live next door to a great power like Russia, you have to pay careful attention to what the Russians think, because if you take a stick and you poke them in the eye, they're going to retaliate. States in the Western hemisphere understand this full well with regard to the United States.”

American political scientist and international relations scholar

John Joseph Mearsheimer is an American political scientist and scholar of international relations, and a professor at the University of Chicago. He is known for his work on great power politics and the theory of offensive realism. His writing and teaching focus on how states compete for power in an anarchic international system. He has become widely associated with realist thinking in international affairs, especially questions of security, rivalry, and the behavior of major powers.