China Teday. China's Foreign Affairs and Intemational Relations % The United States and China set up liaison offices in each other 's capitals in 1973 and bilateral trade grew unevenly throughout the decade Peoples diplomacy" played an important role, as most exchanges of delegations were sponsored by friendship associations School of politics and International relations 2013/4/12❖ The United States and China set up liaison offices in each other’s capitals in 1973, and bilateral trade grew unevenly throughout the decade. “People’s diplomacy” played an important role, as most exchanges of delegations were sponsored by friendship associations