President Truman had the urge to use the atomic bomb against Japan because the American casualties would continuously rise unless the Empire of Japan surrenders. The thing that would make Japan surrender would be a cataclysmic event, and the bombing of Hiroshima and Nagasaki happened.
An effect of the discovery of the New World in the late fifteenth century was a global exchange of plant life as different plants were transported to America where they thriwed, but different plants were also transported back to Europe and thriwed there as well.
The Niles water would be collected during the summer season because that's when the water would rise. This helped the Egyptians to grow their crops however the Nil would often flood and cause destruction to the surrounding land and crops.
