With the question: "To what extent do you agree or disagree", you should give a direct answer in your thesis statement, whether you agree or disagree the issue. In your introduction, especially your thesis statement, I think it's rather ambiguous.
I believe that they are important somehow, but not essential.
- Using the word "important" means that you agree with the World sport event. However, the adjective "essential" shows a negative aspect of international sport events.
Here is my thesis statement:
In my opinion, despite some disadvantages, the worldwide soprt competitions are vital in reducing global strains and realeasing nationalistic feelings in the best ways.