No summary can describe it.
I clicked it without reading your username, but as soon as it started I knew you were the same one that made No Music No Life. You have an outstanding style of animation, it's original, fresh, smooth, and used in great manner.
However the message to me comes from the mind of a child.
As long as humans have freewill, they will want more, or at least better things than the ones they have. People call it "having goals", I call it materialism for the most part. This endless struggle for having anything and everything is a big factor for wars. Unfortunately, if you ask me, the only solution to this is to strip all human beings of individual thought and brainwash them to do good. Which isn't a bad idea.
But you see, even in the most ferral, animal, natural habitat, war is always present. Be it to survive, or to simply expand. There is no peace without war, there's no appreciation of peace without war. There's no hatred towards war without peace, you simply can't have one without the other.
All that being said, having the mentality of a child might not be such a bad thing. Now if the message could be implemented instead of being merely shown.
Congrats on this submission, on all your previous ones, and the ones the future will bring. You really stand out.