It was important because segregation and discrimination had reached a point were it was no longer tolerable To state that African Americans should join the war because a win would be a double victory over racism abroad and at home.
The three branches of the government are the Executive, Legislative, and the Judicial branch. https://www.google.com/search?q=three+branches+of+government&rlz=1CAHPZQ_enUS786US786&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi5v5jGr7HdAhVJTd8KHY9RCS8Q_AUICigB&biw=1536&bih=720#
If you're referring to the post WW2 period, then it was fairly simple, the United States wanted to create a democratic liberal country that would share their political goals in Europe, while the Soviets wanted to make it into a Communist state that would share their goals and ideals in Europe. Each would have their own central European country to control the remainder of Europe.
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As the war dragged on, the unions advantages in factories, railroads, and man power out the confederacy at a great disadvantage
