How did nationalism indirectly contribute to imperialism?

In powerful countries, nationalism can lead to imperialism. Nationalism can be defined as the idea that your country is superior to all others. If people feel nationalistic, they might start to want to prove that their country is better than the others. One way to prove this is by taking an empire.

powers  are  denied  to the  national governmentin three distinct ways: some  powers, such as the  power  to levy duties on exports or prohibit the freedom of religion, speech, press, or assembly, are expressly  denied  to the  national government  in the  constitution.

b) the confederacy had to pay all union war expenses.