Roosevelt's list of additional attacks carried out by the Japanese serves to prove the severity of the threat. He says that the Japanese have "undertaken a surprise offensive extending throughout the Pacific," which includes numerous American interests.
Therefore, his main purpose is to further develop the sense of betrayal. He is making clear that more than Pearl Harbor has been attacked -- the entire Pacific has been.
Imagination And Fear In “The Fall Of The House Of Usher” By Edgar Allan Poe And “The House Taken Over” By Julio Cortazar. Imagination overcomes reason when you don't know who or what something is.
