September 21 in history, these intelligence were sent to the US president

情报历史上的9月21日，这些情报被递交给时任美国总统

Intelligence History on 1961 September 21
Intelligence History on 1962 September 21
Intelligence History on 1963 September 21
Intelligence History on 1964 September 21
Intelligence History on 1965 September 21
Intelligence History on 1966 September 21
Intelligence History on 1967 September 21
Intelligence History on 1968 September 21
Intelligence History on 1970 September 21
Intelligence History on 1971 September 21
Intelligence History on 1972 September 21
Intelligence History on 1973 September 21
Intelligence History on 1974 September 21
Intelligence History on 1976 September 21