Final answer:
Richard Nixon was the U.S. President who visited Communist China in 1972, which was a remarkable event that helped establish formal diplomatic relations between the two countries and affected international Cold War dynamics.
Step-by-step explanation:
The U.S. President who made a surprise visit to Communist China in 1972, paving the way for establishing formal diplomatic relations, was Richard Nixon. This visit was a significant geopolitical move during the Cold War era, where the United States sought to exploit the Sino-Soviet split and gain several strategic advantages. Nixon's unexpected trip to Beijing, also known as playing "the China card," reversed decades of U.S. diplomatic sanctions and hostility towards the People's Republic of China. Nixon met with Chairman Mao Zedong and Chinese premier Zhou Enlai, ending with a promise of establishing trade and eventually full diplomatic relations. This historic visit also had implications on the U.S. relationship with the Soviet Union and the ongoing war in Vietnam.