Final answer:
Sectionalism is the idea of prioritizing the interests of a certain area of the country over that of the nation.
Step-by-step explanation:
The idea of putting the interests of a certain area of the country over that of the nation is called sectionalism. It refers to a strong sense of loyalty and concern for the interests of a particular region or section of the country. This can lead to conflicts and tensions between different regions or states within a country.