Power is a combination of strength and will.
The strength can be physical, mental, or economical. However it's the (will) that pushes one person or nation to be more aggressive in accumulating power and willing to demonstrate it in order to have things (their) way. The elephant is much larger than the lion and yet the lion is referred to as being "The King of the Jungle".
Power is rarely just "given" to an individual or nation for that matter. They want it, take it, demand it, and are willing to fight to keep it. Some animals and people are more passive by nature.
On the other hand some people are content with letting others shoulder the responsibility that comes with power and they're willing to be a follower in order to have protection.
Power in of itself is not a bad thing it's how one uses power that makes all the difference.