World leaders use nationalism both to ensure that they will remain in power to and try to advance the interests of their country.
When leaders can tap into nationalism, they are able to make people support them. There are many instances of this. Chinese officials, for example, have been known to encourage people to act nationalistically towards Japan or towards the United States. When they do this, it allows them to make their people feel as if they are all united behind a common goal. The people then stop worrying about the government’s shortcomings and focus, instead, on their shared nationalism and their anger at the outside.
When leaders tap into nationalism, they can also sometimes advance their countries’ interests. This is because their people will be more motivated to act in certain ways. For example, their people may be more motivated to work hard and to improve their economy. This was what happened in Japan and South Korea in the post-WWII era. In extreme cases, they may be willing to undergo great hardships, such as those that people undergo during a war.
In short, nationalism can be used as a motivator and a unifier to promote both national and personal goals.