Why was nationalism an important factor in world war 1?

Locate an article online from a news source that illustrates at least one determinant of supply. write a summary of the article, list the determinant(s) that were discussed in the article, and give a brief explaination of the effect of the determinant(s). you don't need to write the entire thing out, just find a source and tell me what i should include. i'm not the best at some parts of economics, and this is one of the parts i suck at.