Answer:
Read below
Explanation:
1: Barbarians kept on attacking
2: Internal stability like the killing of Julis Ceaser
3: Ethnic groups inside the Roman Empire that wanted to be free
4: People were hungry for power
5: Failing economic system
6: The Roman Empire being split in two
7: Some people didn't want to change there religion
8: Rise Of Islam ( later years )
9: Different cultures
Cambodia and Lao--these neighboring countries were the path for the North Vietnamese to reach the southern parts of Vietnam more quickly.
Cambodia and Laos would be the located of the HoChi Minh Trail which was the supply line from the North to the South. Many parts of the trail were underground and difficult to get rid of. The US resorted to air strikes of the two countries which was controversial because they were technically neutral areas.
Yes, it would never hurt for a country to be more powerful and stronger /more protected
