He also served as a delegate to the United Nations General Assembly from 1971-1972 and as chairman of the U.S. delegation to the Interparliamentary Union from 1970-1972 and 1978-1980 . He also served as a delegate to the United Nations General Assembly 1971-1972 and as chairman of the U.S. delegation to the Interparliamentary Union from 1970 â `` 1972 and 1978-1980 .