Jeffrey LewisExtended Deterrence

The next couple of weeks are all extended deterrence for me — I am teaching a course on the subject in Monterey, focusing on the decision to retire the TLAM-N as a case study, and making some remarks at another event back in Washington the week after.

And, I’ve penned a short op-ed for the Lowy Institute’s blog, The Interpreter, that starts with a heresy:  there is no such thing as the nuclear umbrella.

Then I move on to all sort of other impermissible suggestions, concluding that maybe we should stop talking about extended deterrence as though it were somehow distinct from what I am inclined to call core deterrence — the central mission of nuclear weapons to deter nuclear attacks against the US, our forces abroad and our allies and partners.

Rory Medcalf asked me to cross-post it, but really, you should go to The Interpreter and read all the submissions (and not just mine!) in what is a lively debate on the question “Is Extended Deterrence Dead?” Rory, George Perkovich, Bruno Tertrais, Shen Dingli and others have penned thoughtful contributions.


  1. Amy (History)

    Could you kindly tell us how the two terms “extended deterrence” and “core deterrence” are defined precisely in you and your colleagues’ reading?

  2. John Bragg (History)

    You say that there is no extended deterrence or no nuclear umbrella, but that is a rhetorical shell game. You extend “core deterrence” over three distinct areas–“the United States, our forces abroad and our allies and partners”

    A nuclear attack on
    1. United States territory,
    2. US forces abroad or
    3. a US ally
    are not automatically the same. Nuclear attacks on Omaha, Okinawa or Osaka do not carry the same certainty of retaliation, or the same probability of maximum retaliation. You elide the distinctions when you classify them all as “core deterrence.”

    • Amy (History)

      I raised the same point and asked Jeffrey to define what he means by extended deterrence and core deterrence. (His use implies the same thing by both terms).

      He did not publish my comment or define what he means, yet.

  3. rwendland (History)

    Jeffrey, do you have an updated version of your great December 2009 Tomahawk2.pdf paper on this topic, which is marked “Draft: Not for citation or attribution”? In the UK context it is a useful paper to refer fans of a less-than-Trident replacement to, and it would be nice to cite a non-draft version. Thanks.