Hello. You did not inform the article to which the text refers, which makes it impossible for your question to be answered. However, I will try to help you in the best possible way.
The conflict and tension of a war or a pre-war period can present great threats to a country. The author can use this concept of threat and fear to explain why countries go to war. The fear of being attacked, or of being harmed in the face of major conflicts between governments, makes countries want to protect themselves and weaken those who are causing the threat. You should look for this type of concept in your article to arrive at the correct answer.