Roosevelt knew why fear itself ought to be feared the most. It's because the power of fear is great. Fear is to an A-bomb what an A-bomb is to a Q-tip. It's the oldest human emotion, the great grandfather of anger, violence, murder and revenge, more primal by far than love and hate which are mere concepts by comparison, spectral definitions of the way things could be if only they weren't as they are. Fear, on the other hand, takes matters into its own hands, seizes the entire body, scoops out the soul, puts in the shell an absolute obedience to a nakedly insane purpose which is to kill its own kind and ultimately itself for reasons universally unremembered once things get going. It is fear that causes humanity to turn on humanity and commit atrocities less inhuman than dishuman, fear that puts a mother on her knees with pins in her mouth to make final adjustments on her daughter's suicide vest. Fear sends willing armies, makes cannonballs of its own children, grips all the people in a single fist and punches the daylights out of itself. Fear, therefore, is the most important tool in the world leader's toolkit, and those leaders who master it best will control us all for generations to come, or until the very moment we finally wise up.