Answer:
Nationalism advantages - promotes sense of national identity, unifies people
Nationalism disadvantages - conflicts with views of others, diminishes rights of others
Military preparedness advantages - deters/defeats hostile aggression, gives people a sense of safety
Military preparedness disadvantages - seen as threatening, could cause a war draft
Step-by-step explanation:
Nationalism is basically when a country unifies for a common goal. It could be through use of symbols, too. For example, everyday in school we stand and say the Pledge of Allegiance together. However, sometimes a country can discriminate against a group of ethnic people if the majority doesn't like them.
Military preparedness is as the name says: being ready for war and having a strong military. These are good things and can make people feel safe. However, a potentially opposing country could see this as a challenge which is could be a cause of war.