
Historians considering the short border war of 1979 between China and Vietnam have long concluded that the Chinese invasion into the north of Vietnam – an attempt to exert some control over Vietnamese expansion in Indochina — was a military failure. Vastly superior Chinese forces were met with determined resistance by a regular Vietnamese force capable of successful guerrilla tactics. The analysis continues that after heavy losses Chinese forces sulkily withdrew back across the border, never to trouble the peace again.
In full: https://thediplomat.com/2019/05/the-sino-vietnam-war-and-chinas-long-route-to-winning/

