Peace is the theory of universal love and acceptance.Sadley peace cannot be acheived because to do so would end all conflict and thus bring about the end of the world because there would be nothing left for humanity to argue about so life would have no reason to continue.
Something that seems so hard to reach because everyone has a different view of it. Peace means to be even, safe, no fighting, killing. Sometimes peace can only be achieved by death of those who disorient peace.
Hitler is dead, he killed over 20 million people but now that he is dead he can't harm anyone.