Some Viet rioters running amok is nothing if comparing to hundreds thousands of young Chinese burning everything killing everyone during culture revolution.
For centuries we have been the peace keeper in SE Asia, ending Islam in southern Vietnam, stopping the expansion of Islam and Hinduism into Indochinese heartland, restoring borders of Laos, Cambodia to Thailand, ending the genocide in Canbodia, stopping the expansion of other powers as Mongol, Manchu, Siam. To mention ending the French colonialism, US presence in Vietnam, uniting the country. Just to name a few.
What have you done in the history?
What are your achievements as a big country, let say 400 years?
Virtually nothing. Moreover, you tend to create chaos.
As a loser of history
Japan holds a large part of East China Sea.
South and North Korea are still at war.
Taiwan continues to be a country.
Russia keeps a lot of China as booty.
Mongolia becomes a country.
The only thing you brag right now is bullying Vietnam and Philippines.
What a shame for a big country with more than a billion of people.