China keeps probing it's "friends and foes," which very much follows Sun Tzu's advice to probe your enemies and see how they react. It also uses Weiqi (Go) strategy to establish small territories with the intent to eventually tie them to larger territory. Sometimes you end up pissing off your friends and the most recent blow back is violence against Chinese citizens and business, in Vietnam. I guess this is what happens when you explore for oil & gas in areas that are claimed by Vietnam. Whoops.
Oil drilling rights are at the heart of a dispute between Vietnam and China that turned violent over the past week, causing China to consider scrapping some of its bilateral trade agreements with the frontier market to its south. Forbes