<Ul> <Li> New Year's Day Battle of 1968 </Li> <Li> Khe Sanh <Ul> <Li> Ban Houei Sane </Li> <Li> Lang Vei </Li> </Ul> </Li> <Li> Phase One Offensive <Ul> <Li> Saigon </Li> <Li> US Embassy </Li> <Li> Cholon and Phu Tho Racetrack </Li> <Li> Tan Son Nhut Air Base </Li> <Li> Joint General Staff Compound </Li> <Li> Bien Hoa and Long Binh </Li> <Li> Hue </Li> <Li> Quảng Trị </Li> <Li> Coburg </Li> <Li> Lo Giang </Li> </Ul> </Li> <Li> Hop Tac I </Li> <Li> Patrick </Li> <Li> Truong Cong Dinh </Li> <Li> Lima Site 85 </Li> <Li> Quyet Thang </Li> <Li> My Lai Massacre </Li> <Li> Carentan </Li> <Li> Pegasus </Li> <Li> Toan Thang I </Li> <Li> Burlington Trail </Li> <Li> Scotland II </Li> <Li> Delaware </Li> <Li> Allen Brook </Li> <Li> May Offensive <Ul> <Li> Landing Zone Center </Li> <Li> An Bao </Li> <Li> Kham Duc </Li> <Li> Coral--Balmoral </Li> </Ul> </Li> <Li> Mameluke Thrust </Li> <Li> Robin </Li> <Li> Thor </Li> <Li> Pocahontas Forest </Li> <Li> Somerset Plain </Li> <Li> Phase III Offensive <Ul> <Li> Duc Lap </Li> </Ul> </Li> <Li> Vinh Loc </Li> <Li> Maui Peak </Li> <Li> Meade River </Li> <Li> Hat Dich </Li> <Li> Speedy Express </Li> </Ul> <Li> New Year's Day Battle of 1968 </Li> <Li> Khe Sanh <Ul> <Li> Ban Houei Sane </Li> <Li> Lang Vei </Li> </Ul> </Li> <Ul> <Li> Ban Houei Sane </Li> <Li> Lang Vei </Li> </Ul>

How and when did the vietnam war start