Manifest Destiny was largely led and carried out by white americans seeking the westward expansion to increase the boundaries of the United States. African Americans were impact largely because as westward expansion continued new states were brought into the union with legalized slavery in places like Texas. This had an overall negative impact on African Americans by increasing the demand for slavery and expanding the institution of slavery westward. For the Native Americans Manifest Destiny was a major catastrophe leading to the ethnic cleansing and removal of Native Americans from their homes and lands. This removal often occurred with force with high rates of violence.
The answer is the second one or Supranationalism
Uncle Tom's Cabin was a novel written by Harriet Beecher Stowe about slavery in the south. When people read it, they started to realize and be informed about what slavery was like, so more people started being opposed to slavery (because before this, people in the north tended to not care) and more people became abolitionists.
