How was the Cherokee removal act connected to Manifest Destiny and westward expansion?

After the completion of the Louisiana purchase by Thomas Jefferson, many acts were put in place after the sudden large expansion of United States' land. The purchase drove "Both the  population and economy to the west." (via. Smithsonian American Art Museum)

The Cherokee Removal Act was one of many acts to abolish the territory loosely held by several groups of Native Americans in the land now owned by the United States. Once removed or relocated, the Native Americans' left behind space would leave great opportunity for "economic prosperity to  raise cattle, wheat, and cotton, and harvest timber and minerals."

social contract theory, nearly as old as philosophy itself, is the view that persons' moral and/or political obligations are dependent upon a contract or agreement among them to form the society in which they liv