The correct answer to this open question is the following.
What "gang outlaws" meant when stated by Franklin d Roosevelt in 1940, was that without that bunch of enemies, meaning to Germany, Italy, and Japan, the Axis in World War II, peace could not be possible.
US President Franklin D. Roosevelt delivered the speech called "The Arsenal of Democracy," on December 29, 1940. In the speech, Roosevelt referred to these three countries as a threat to the United States and democracy. He said that if Great Britain went down, the risk was that an alliance of dictators would try to control the world. Then he added that "there can be no ultimate peace with this gang of outlaws."