It seems that everything we put Nato players is misinterpreted. Some players are so self-centered that they think we seek profit from war. Not everything boils down to that, what my colleague Mencey has commented is reasonable. I think we should not lose the essence of a medieval game.
I put a link of 10 impregnable fortresses.
https://viajes.nationalgeographic.com.es/a/10-inexpugnables-fortalezas-medievales_9140
Why do you think they built them?
They also lost time and work to climb those walls to benefit from them.