So other colonies could trade them for their one crop , gets them more money you can say
I'd think the main benefit was independence from Western powers in the French and the Americans. Pretty big deal, even with one million killed from fighting. Maybe one could argue that the war also resulted in stronger government that was able to resist Chinese pressure, which allowed Vietnam to defeat China when they fought in 1979. Vietnam resisted the Japanese, the French and the Americans so it is a stretch to suggest they needed a war to defeat the Chinese as well, but the war did leave Vietnam unified.
There is one line of thinking that the North allowed the Viet Cong to be crushed once
in 1999 founded 3 bodies , 2 FOR 2 children and one for one girl and they was very good save from icy conditions the height of their burial place at the top of the mountain was known, and the older girl was known as LaDoncella, the Virgin. and the studies says that in the lost months they was good care and spicily the girl , Suggests that the sacrifice of children was important to the Inca Empire, which used children as sacrifices all the time and in all circumstances; in natural disasters, in times of war, in order to be close to the gods and to their satisfaction. This violent weather was, in accordance with their beliefs, The child chosen for sacrifice.
Federalism, D, hope this helps :)