@ EastSea
You do talk a lot of nonsense. How can Japan be China's master by claiming Manchukuo? gpit never said anything that China is Vietnam's master. He only said that Vietnam belonged to China for a very long time. Actually to be more specific a part of the current Vietnam was part of China in a couple of Chinese Dynasties. Look at this animation.
Here are some facts for you to read.
Jin Dynasty 1115 - 1234 created by Jurchen people (ancestors of the Manchu people)
Yuan Dynasty 1271 - 1368 established by Kublai Khan (grandson of Genghis Khan)
Ming Dynasty 1368 - 1644 Mongols rule ended, this dynasty was established by the Han Chinese
Qing Dynasty 1644 - 1912 This dynasty was created by the Manchu people
1858: Treaty of Aigun signed between Russian empire and empire of the Qing Dynasty
establishing the modern border between Far East Russia and Manchuria
1904: Russia occupies Manchuria, Japan declares war with Russia
1905: Treaty of Portsmouth signed, Russia agrees to return sovereignty to China.
1931: Japan invaded Manchuria
1932: Manchuria becomes puppet state Manchukuo
1937: Japan invades China, start of 2nd Sino Japan war
1945: End of WW II, Manchukuo abolished after Soviet's invasion
China has always been ruled by different ethnic people, by Han Chinese, Mongols, Manchuria people etc. Even Manchuria's ancestors the Jurchen ethnic were part of China (see Jin Dynasty). Manchukuo is just a puppet state created by the Japanese when they invaded China.
You seem so proud to tell us how you Vietnamese beat the French, Americans and Chinese. How we wanted to invade Vietnam.
You forget that Vietnam was divided in North and South. America supported the South while China supported the North.
If it wasn't for Soviet Union and China , North Vietnam probably would have lost to the South.
In the summer of 1962, Mao Zedong agreed to supply Hanoi with 90,000 rifles and guns free of charge. Starting in 1965, China sent anti-aircraft units and engineering battalions to North Vietnam to repair the damage caused by American bombing, rebuild roads and railroads, and to perform other engineering works. This freed North Vietnamese army units for combat in the South.
Sino-Soviet relations wasn't good after the Soviets invaded Czechoslovakia in August 1968. In October, the Chinese demanded North Vietnam cut relations with Moscow, but Hanoi refused. China began financing the Khmer Rouge as a counterweight to the Vietnamese communists. The Khmer Rouge launched raids into Vietnam in 1975–1978. Vietnam responded with an invasion that toppled the Khmer Rouge. In response, China launched a brief invasion of Vietnam in 1979. After China retreated Vietnam occupied Cambodia.
1) North Vietnam didn't defeat America, USA just retreated from the Vietnam War
2) China didn't want to occupy Vietnam, they just helped Khmer Rouge.
3) China and North Vietnam suffered heavy losses, China decided to retreat just like the Americans.
You and many Vietnamese probably feel like you people have won the war while China and USA just retreated. Unlike Vietnam China had no plan to occupy because that's what Vietnam did with Cambodia.
from ancient time, before Han Dynasty in China. 
