The United States maintained neutrality up until the point where Japan bombed Pearl Harbor. After that, it was impossible for the US to keep to itself.
Okay what are the questions so i can answer
The Korean War was the first battle of the Cold War, and first major proxy war fought between the United States and a Soviet communist supported enemy. A proxy war occurs when one or more opposing powers instigates a war and then uses third parties to fight on their behalf.
Since during the Louisiana Purchase, we purchased so much land(technically the whole entire United States). Manifest destiny is our belief to spread from sea to shining sea so, we were motivated to expand to that new land we purchased. That would make the thirteen colonies less crowded and over populated.
