Answer:
Democrats vs. Republicans - P
This represents a political conflict because the Democrats and the Republicans are the two main political parties of the United States.
the Cold War - P
The Cold War was mainly a political conflict between the two world superpowers at the time: the Soviet Union and the United States. However, it was also an economic and ideological conflict, between capitalism and communism.
Protestants vs. Roman Catholics - R
This is a religious conflict because they are both religious denominations within Christianity, a major world religion.
isolationism vs. internationalism - I
This is an ideological conflict. Isolationism and Internationalism are two opposing ideologies about the way that nations should relate with other states in the global stage.
the Crusades - R
The Crusades was mainly a religious conflict, between European Christianity, and Middle Eastern Islam. However, it was also a political and economic conflict.
free trade vs. trade barriers - E
This is an economic conflict because two opposing economic views about trade are being challenged.
colonialism vs. nationalism - I
This is an ideological conflict. Colonialism and nationalism are two ideologies that can be in conflict with each other, although they were often allied ideologies in real history.