The world is just like the animal world. Lions will eat meat, or they will starve to death. The country can produce food if it wants land, and it can control the people if it has food. People will rebel if they don't eat. When the land is occupied by other countries, the food produced will decrease. Because of class problems, the food distributed to the people will be reduced, the people will riot and overthrow the government, anti-government forces will prevail, and the political situation will be unstable. This is just a simple example. The nature of a country is more complicated than that of an animal. But the essence is basically the same.