I see a lot of very ignorant comments in this thread. Vietnamese are Vietnamese and Chinese are Chinese.
People from Guangdong etc. migrated to Vietnam in mass when Japanese agression happened. These people living in Vietnam now are 100% Han Chinese not "ethnically related to Chinese" as some of you claimed. They still speak Teo Chiu (dialect of Chinese) and consider themselves Chinese. They also tend to marry other Han Chinese in Vietnam. There are a few odd balls that marry Viet husbands/brides but those are the minority of ethnic Han in Vietnam.
Vietnam was never "ethnically related to Chinese". What you think of those "Vietnamese" are simply Han migrants that migrated to avoid the war.
Some Chinese even migrated very far to the South of Vietnam to areas onced belonged to Cambodia. BUT they got surprised when Vietnam annexed those parts (they thought they were building a future home in Cambodia but hoho God played a trick on them) so they are now stuck in Vietnam, and folks like you think they are Vietnamese but they are not!
So mostly, I see people hyping Vietnam to be the next Asian tiger because they are genetically related by blood. My rear end!
Chinese make up a minority in Vietnam. BUT they're the ones driving the majority of economy in Vietnam (because the real Vietnamese is lazy and loves to biggot about China on forums). What you people called Hoa people (Hua Ren) in Vietnam are simply emigrant Guangdonians decades ago, not full blooded Vietnamese that are somehow magically "ethnically related to Chinese".
Unfortunately, there are no Chinese control of the politics in Vietnam.
Vietnam is a country that could backstab China at anytime. Those in power in Vietnam are not the ethnic Han nor their descendants that migrated there due to Japanese agression. The VCP don't identify with China's ideology nor goals. They're simply in it to profit from a rising China!
The less China has to do with Vietnam (other than show some superficial friendship) the better for her future!