Nazis believed that Germans was the superior race in the world and despised everyone especially Jews and couldn't tolerate them. As a result, he persecuted in hope that the entire race will vanish. He also liked Germans with blue eyes more than with brown eyes.
Agriculture was key to the development of modern "civilization" because by being able to grow food rather than getting it through trade or hunting, people were able to stay in one place instead of having to be where the food was. This also led to jobs because people became highly skilled in growing crops.
This was the first peacetime conscription bill enacted in the USA, requiring all men between 21 and 45 to register for the draft. It was drafted before the US joined WW2, and was part of a plan for the US to be prepared if war ever did break out, as it did.