You Indians like to brag about the Vietnamese bravery. China help Vietnam fought the French, and then fought the USA, without China help, Vietnam can not win, at lest 20000 Chinese soldiers were in Vietnam directly in the war, responsible for air defence and logistic, many weapons were from china. In 1979, China have problem with Vietnam because Vietnam invasion of Cambodia, China give Vietnam pressure to withdraw, and in this war, Vietnam for sure suffer much more loses than China, but China found out that after the disastrous culture revolution, China army need training, since 1979 until 1989, for ten years, we forget Vietnam on the border, the border is the mountain ridge, China took all the ridges, the war not big scale, but very bloody. Vietnam prove to be inferior than China for the spirit and planning. For this 10years, China business as usual, all armies sent some the representative to fought this border war as training, the same time china make a big development, but Vietnam lost whole 10 years, and ask to resume a normal relation with China.
How come Vietnam can be superior then China? Vietnam were founded by China, The first three cities ( or the governing body ) were established 214BC in north of Vietnam, and immigrated many people there, at 204BC, the Qin dynasty was over throw by a war, the governor of this place ZHAO TUO declared himself the king, the year 111BC, HAN Dynasty bring this rear back again. For the next 2000years, when china strong, Vietnam is part of China, when China are in chaos and weak, Vietnam semi independent, until year 1884, the French take over Vietnam, and invented a language for Vietnam, before the Vietnam written all in Chinese and most of the kings were from mainland of China.