Prominent nuclear scientists warned the USA that being last in the race to make a nuclear bomb may well be fatal to person and freedom.The USA started and completed the "Manhattan Project",the most expensive and secretive undertaking by this or any country at the time.It turned out the war was won without it, but it's undertaking was seen as national security of the highest order.This is only one answer but certainly one that must be discussed.
National Security act
National Security Act
That America's national security involved world security
Norman Angell has written: 'Commercial security' -- subject(s): Causes, Economic aspects, Economic aspects of National security, Economic aspects of War, National security, War, World War, 1914-1918
National security during wartime.
National Security Act
Probably due to the increased mechanization of the combatant forces. But frankly, the production of national industries was a key factor in many conflicts prior to the first world war.
The National Security Act of 1947, which was signed into law by President Truman, restructured the intelligence and military agencies within the U.S. government. This was done after World War 2.
Duration camps during World War 2 were used to house threats to national security and captured enemies. Duration camps are often referred to as refugee camps.
National Security Council
National World War II Memorial was created in 2004.
It's purpose was to prepare U.S. citizens for war.