I think aggressive ambition of conquest and empire building
The main goal of imperialists was to enrich the home countries. They would colonize Africa and use the colonists as cheap labor force, often as slaves, and would produce things that were cheaper and would take all of their resources and sell them or manufacture things from them. This would bring wealth to the colonizer but no wealth to the colony itself.
C the fugitive act was enforced
Answer: The President has the power to veto.
Explanation: You can override a veto by each chamber of Congress votint on a bill vetoed by the President. To pass a bill over the president's objections requires a two-thirds vote in each Chamber.
What the three cases have in common is that they were all victories for the people and their amendment guaranteed rights against states who wanted to obstruct those. The first case was about preventing states from limiting freedom of speech, the second was about preventing illegally obtained evidence from being used in court, and the third was that the states have an obligation to provide a lawyer to criminals if they can't pay for them.