In fact, as soon as it declared independence, Ukraine should have been quietly encouraged to fashion its own nuclear deterrent.

John Mearsheimer’s quote reflects his belief that Ukraine, upon declaring its independence, should have been supported in developing its own nuclear deterrent. He suggests that by acquiring nuclear weapons, Ukraine could have better secured its sovereignty and protected itself from external threats, particularly from Russia. Mearsheimer’s argument is grounded in the idea that nuclear deterrence is a key factor in maintaining national security, especially for countries in volatile regions.

The origin of this perspective stems from Mearsheimer’s expertise in international relations and his views on realpolitik, which emphasize the importance of power and security in global politics. In the case of Ukraine, Mearsheimer contends that a nuclear arsenal would have served as a powerful deterrent against any potential aggression, particularly from a nuclear-armed Russia. This recommendation aligns with his broader belief that states must prioritize their own security and capabilities, especially in the face of an unpredictable and often hostile geopolitical environment.

Mearsheimer’s comment also alludes to the historical context following Ukraine's independence from the Soviet Union in 1991. At that time, Ukraine inherited a significant portion of the Soviet Union’s nuclear arsenal, which it later agreed to give up in exchange for security assurances through the Budapest Memorandum. Mearsheimer critiques this decision, arguing that by relinquishing its nuclear weapons, Ukraine forfeited a crucial means of self-defense, leaving it vulnerable to Russian aggression.

In essence, Mearsheimer’s quote advocates for nuclear deterrence as a vital means of ensuring the security and independence of smaller nations like Ukraine. He believes that Ukraine’s independence could have been more secure if the country had been encouraged to maintain or develop its own nuclear capabilities, thus strengthening its position against foreign threats and pressures.