Answer: Nationalism can basically be defined as the idea that your country is superior to all others. Also if people feel nationalistic, well they might start wanting to prove that their country is better than others. So basically one way to prove this is by taking an empire. Also nationalism is a belief that one's country is the best. Imperialism allows a nation to just expand it's borders and to gain more valuable raw materials and trade markets. Nationalists just believed that their nation's values were just the best and that these had to be spread to the developing world.