Well, the Vietnamese better rethink that decision! Kerry still secretly holds the rank of a field grade officer in the Vietnamese military intelligence service and still has a lot of clout back in Hanoi. He could make it difficult for a person relatives who are still there. Kerry communicates with his superiors in Hanoi through contacts in the UN Mission in NYC. In fact, Kerry's service with and rank in the Vietnamese military is covered in Kerry's US military records and was, in part, the cause of his being court martialed and thrown out of the US Navy. It is all in the documents!
Do you have a link to those documents?