Fear is the enemy of logic.

Uit een interview met Playboy in 1963.

Fear is the enemy of logic. There is no more debilitating, crushing, self-defeating, sickening thing in the world — to an individual or to a nation. If we continue to fear the Russians, and if they continue to fear us, then we’re both in big trouble. Neither side will be able to make logical, reasoned decisions. I think, however, that their fear and concern over the ideological balance of power in some areas is far from irrational. Our concern over a Sovietized Cuba 90 miles from Key West, for instance, must be equated with Russian concern over our missile bases surrounding them. It is proper that we should be deeply concerned, but we must be able to see their side of the coin — and not let this concern turn into fear on either side.