Keval Patel also wrote about throughout history, there have been positive and negative effects of nationalism. The positive example given was the world cup.
By bringing people from each country together, fans were united by cheering on their teams on whether they win or lose. There was a strong sense of pride and confidence.
When the American colonists worked and came together to unite against a common enemy, this illustrated when American nationalism was first developing. However, a negative effect of nationalism is the cause of the first world war one. The European nation desired to show how much power they were wielding. Which