In an ancient days people always think how to be in power. They always needed power. Not even man a single animal too needs power. That's why the survival of fittest suits here. So the stronger one used to win and rule.
The time has changed now. Every one needs power but each and every one cannot overcome the power. Person who uses mind, money and muscle can come to the power. He can do anything what he deserves. He wants to accumulate the resources, gather people, engages them. Here a country or state is regarded as him/he.