The numbers above are estimated death toll of some wars.
The world peace utopia has been a topic for thinkers and philosophers since ancient time. A multitude of theories for achieving world peace have been proposed and debated, for instance, peace through strength (e.g. Pax Romana, Pax Americana), Marxism, democracy, globalization, economic reforms, and religious methods. Different parts (nations) of our world have adopted different philosophies towards ensuring peace, by means of internal or cooperative measures.