Final answer:
The correct answer is centrifugal forces, which refer to the cultural dynamics that lead to the division and potential conflict within a nation.
Step-by-step explanation:
Cultural forces can have a significant impact on a nation. When looking at the factors that either unify or divide a country, we encounter terms like centripetal forces and centrifugal forces. Centrifugal forces are the cultural dynamics that tend to divide a state. Examples of these forces include ethnic conflict, social injustice, poverty, dictatorial leadership, and religious intolerance. These forces might lead to division and potentially to war if they become strong enough. On the other hand, centripetal forces are those that hold a state together. They encourage unity through aspects such as ethnic tolerance, social and economic equity, and shared identity. An example of centripetal force in action would be the surge of nationalism in the United States following the 9/11 attacks, where an outpouring of goodwill and agreement strengthened national bonds. In summary, the question asks which forces divide a nation, to which the answer is that centrifugal forces divide a nation.