Use the excerpt to answer the question.
"By ... the authority vested in me as President of the United States, and Commander in Chief of the Army and Navy, I hereby ... direct the Secretary of War, and the Military Commanders whom he may ... designate ... to [recommend] military areas in such places... from which any or all persons may be excluded."
- Franklin D. Roosevelt,
Executive Order 9066, February 19,
1942
What did Executive Order 9066
indicate about concerns over national security?