Nationalism is a form of patriotism to one's own country. It could also be that the interests of one's country be prioritize than that of the other nations. Nationalism started way back in the early 20th century in Europe causing the World War 1. It gave the people confidence in their country including their government and military thus it caused them to think that their rivals are threatening imperialism and them being aggressive and uncivilized. This then was one of the causes of World War 1.
