How should the security needs of great powers be balanced with the sovereignty of smaller nations on their border? The concept of Spheres of Security limits the activity of other borders of other great powers. Mexico has the freedom to engage in political and economic cooperation with any state, yet Mexico does not have the freedom to host Russian missiles or Chinese military bases. This is common sense and must be applied to all great powers, yet how feasible is such an agreement between the great powers? John J. Mearsheimer is the R. Wendell Harrison Distinguished Service Professor of Political Science at the University of Chicago, where he has taught since 1982. Jeffrey D. Sachs is a world-renowned economics professor, bestselling author, innovative educator, and global leader in sustainable development. Follow Prof. Glenn Diesen: Substack: https://glenndiesen.substack.com/ X/Twitter: https://x.com/Glenn_Diesen Patreon: https://www.patreon.com/glenndiesen YouTube: https://www.youtube.com/@GDiesen1 Support the channel: PayPal: https://www.paypal.com/paypalme/Diesen79 Buy me a Coffee: buymeacoffee.com/gdieseng Go Fund Me: https://gofund.me/09ea012f