After communist North Vietnam's victory over U.S.-backed South Vietnam in 1975, the United States and Vietnam had minimal relations until the mid-1990s. Since the establishment of diplomatic relations in 1995, overlapping security and economic interests have led the two sides to expand relations across a wide range of sectors. In 2013, President Obama and his Vietnamese counterpart announced a "comprehensive partnership" that is to provide a framework for moving the relationship to a "new phase." A key factor driving the two countries together is a shared concern about China's increased assertiveness in Southeast Asia, particularly in the South China Sea.