Everything you said, sounded nice but nothing realistic there because you can't stop war from happening. War has always being a part of the human race existence. People have been fighting from the past, countries have been fighting too. It was war that brought colonization and development to some countries. Stronger countries will always want to rule the weaker ones and the weak ones will be looking for a way, they'll be on top and be controlling.
What causes war is greed and hunger for power. Russia wants to control Ukraine, USA wants to control others and so forth. The government of countries causing war all over aren't satisfied with the power that they have, they want to control more land and resources but they're getting a resistance from the country they want to conquer. The easiest way to end all war is for all human race to end and we exit this earth, only then will earth have peace.
You are on point mate, war has been in existence since the beginning of humanity and we are have our flaws that could lead to conflicts and hereby causing war to happen. Hunger for power, greed and the desire for control has been the major contributors of war, however, as humans we also have the capacity for empathy, cooperation and compassion that can bring us together and foster peace. This generation has been messed up but peace can be achieved if we work on the next generation to come after us and to get there we need to start with small steps by teaching our children the value of kindness, empathy and respect for others. If only we can encourage open communication, listen to each other and understand each other's perspectives then the world would be a better place.