In a blog post for his site Defusing the Nuclear Threat, Martin Hellman quoted from Secretary of Defense Chuck Hagel’s recent speech honoring Gen. Robert Kehler, the outgoing chief of STRATCOM, the military command in charge of nuclear weapons, and cyber- and space warfare. “Perfection must be the standard for our nuclear forces,” Hagel said at one point. At another: “there is no room for error.”

Hellman is a professor emeritus of electrical engineering at Stanford and one of the inventors of the technology that secures credit card transactions on the Internet. In recent years he has become an authority on nuclear risk ― the calculations in his essential 2008 article Soaring, Cryptography and Nuclear Weapons pack a punch that will knock the existential wind out of you. Of Hagel’s comments, Hellman notes:

Unfortunately, saying that perfection is required, does not mean perfection is achieved. After all, “to err is human.” So why are we relying on nuclear deterrence when just one mistake could destroy our homeland, and us along with it?

While reading that, I experienced an “epiphany.” Right smack dab in the middle of the word “deterrence” fall the three letters “err”! (I know – kind of sophomoric.) After sharing this with Hellman, he replied, “To err is part of deterrence.” Integral even, I would add.

For their part, nuclear hawks have a convenient habit of leaving human error out of the national-security equation.