The Quarantine Speech was given by U.S. President Franklin D. Roosevelt on October 5, 1937 in Chicago, calling for an international "quarantine" against the "epidemic of world lawlessness" by aggressive nations as an alternative to the political climate of American neutrality and non-intervention that was prevalent at the time. The speech intensified America's isolationist mood, causing protest by non-interventionists and foes to intervene. No countries were directly mentioned in the speech, although it was interpreted as referring to the Empire of Japan, the Kingdom of Italy, and Nazi Germany. Roosevelt suggested the use of economic pressure, a forceful response, but less direct than outright aggression.
Read article on Wikipedia