I don't understand you're question. if you could rephrase i could help
To begin, it didn't promote "peace" as much as it promoted a "cold war" which is the whole point of the name, Cold War.
Nuclear Weapons essentially forced the US and the Soviet Union into an uncomfortable draw.
They knew they couldn't fight each other directly so they fought each other in a series of devastating proxy wars around the world.
Many primary civilizations started in river valleys because for the cities in each civilization an important portion of the population existed in cities. Large-scale farming was a requirement to feed the large populations. Fertile due to flooding the land by rivers was home to lush plant life and an outstanding place to plant and grow crops. The close source of water permitted for irrigation for the large-scale farming as well as drinking and bathing. Water also intended animals and animals meant food so this was another advantage to settling in river valleys. Settling and living in river valleys later main to further development of civilizations and new patterns of living such as trade and communication by means of the river for transportation.
I think it's because slavery costs less...just a guess.
