In my opinion it is justified to invade a country if they kill one of your countries officials. For example ww1 began when Syria killed the duke and his wife of the Austro-Hungarian empire which the Austro-Hungarians inaded Syria.
One of the factors that contributed to the rise of the kingdom of Kush was the brief fall of the kingdom of Egypt. With the Hyksos' conquer of Lower Egypt and their subsequent rule over the same, the kingdom of Kush became the superpower in Upper Egypt.
The Non Aligned Movement struggled to find relevance after the fall of the Soviet Union because was largely based on opposition to the Cold War. The fall of the Soviet Union ended communism hence the movement lost its significance and influence
