As context, Nixon's presidency pursued a policy of Détente with the Soviet Union and the People's Republic of China, or the easing of strained relations between countries. Nixon's ultimate goal was to avoid nuclear proliferation, and end U.S involvement in the Vietnam war. Overtime, it evolved into summits with rivals by Nixon, who became the first president to travel to Moscow, and the first president to visit the People's Republic of China.
Generally speaking, Vietnamese culture was more connected to "Southeast Asian culture" than to China, since China's influence in the region was almost all political in nature.