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Here are some of the weapons first used in WWI. Airplanes, Derigables, poison gas, flamethrower, and tanks. Other weapons that were invented before the war but not used on a wide scale or were not reliable until WWI were the machine gun, submarines, torpedoes, small mortars and very large caliber artillery. WWI also saw the use of the radio for the first time in combat conditions.
Fertile Crescent, which arcs from the Persian Gulf to Turkey and south to Egypt
The Acronym M.A.D. stood for Mutually Assured Destruction.
It is an economic system that features characteristics of both capitalism and socialism. It protects private property while allowing a level of economic freedom in the use of capital, but also allows for governments to interfere in economic activities in order to achieve social aims.