Commentary

Low-Yield Nuclear Weapons (Again)

In

Quote of the week:

“The pattern of the use of atomic weapons was set at Hiroshima. They are weapons of aggression, of surprise, and of terror.”

— Bernard Brodie, The Absolute Weapon

John Donnelly of CQ Roll Call was the first to write about a Defense Science Board report issued last December, “Seven Defense Priorities for the New Administration.” This report reached  the “worrisome conclusion,” widely shared within the “Nuclear Enterprise,” that, “the nuclear threshold may be decreasing owing to the stated doctrines and weapons developments of some states, and with the introduction of new technology.”

U.S. actions were notably missing among the DSB’s list of contributing factors to the increased reliance on nuclear weapons by others.

The DSB then went on to say, “The near exclusive focus on life extension of existing U.S. nuclear weapons was thought… to be limiting flexibility for addressing an uncertain future.” Then came the passage that caused significant commotion – the recommendation

“to provide many more options in stemming proliferation and escalation; and a more flexible nuclear enterprise that could produce, if needed, a rapid tailored nuclear option should existing non-nuclear or nuclear options prove insufficient.”

The DSB mentioned only one possibility in this regard: “lower yield, primary only options.” I presume this means prompt global strike by means of single warhead ICBMs without the big secondary boost. The wording of the DSB report lacks clarity as to whether other low-yield options are deemed worthy of consideration. A primary-only ICBM option doesn’t require much work for the labs. Only one DSB member — Bill Schneider — forthrightly came to the defense of this recommendation. Bill has long supported new warhead development to counter new threats and to pass along design skills to younger folks at the labs.

This time around, as before, a firestorm ensued to hints of renewed interest in nuclear war-fighting. Powerful rejoinders came from many quarters. Hans Kristensen noted that there are at least 1,000 warheads in the U.S. stockpile that can provide low-yield options. Senator Dianne Feinstein weighed in with a reminder that the American public isn’t interested in tailored effects for nuclear war-fighting, and that limited nuclear wars are unlikely to remain limited.

Nor did this aspect of the DSB Report draw support at a House Armed Services Committee hearing where the Vice Chairman of the Joint Chiefs of Staff, Gen. Paul Selva, and the Commander of STRATCOM, Gen. John Hyten, testified. Gen. Selva noted that there are no new requirements “at this time.” Gen. Hyten questioned the very concept of a “tactical” nuclear weapon: “I believe that anybody that employs a nuclear weapon in the world has created a strategic effect, and all nuclear weapons are strategic.” Indian officials use the same rejoinder when dealing with Pakistan’s embrace of low-yield nuclear weapons carried by short-range delivery vehicles. Nor have the U.S. weapon labs reported reasons to resume testing or reasons to certify new, minimal yields.

The only support at the SASC Hearings for the DSB’s recommendation was offered by Keith Payne, who testified, “I particularly think that the very low-yield option is something we have to consider.” I’m not sure what Keith has in mind here, as the lowest option on the B-61 “dial-a-yield” is reported to be 0.3 kilotons. If the problem he has in mind is deeply buried targets, lower yields than that would not be helpful. If the problem is something else, highly accurate, conventional means of delivery would seem a far better choice.

As trial balloons go for new warhead designs for “tailored” deterrence, the DSB report seems tepid compared to earlier campaigns. As noted in this space, these debates have become hardy perennials. I’ve come to believe that the primary driver isn’t really about yield; it’s about honing skill sets at the labs. That being so, this debate seems unlikely to end. More attempts are likely, given the temper of the Republican caucus on Capitol Hill.

There are many strong arguments against tailored nuclear deterrence. Low-yield weapons with short ranges — or no ranges — are inherently the least safe and secure. Belief in escalation control is pure hubris. But for me, the strongest argument is how much effort has gone into preventing the battlefield use of nuclear weapons for the past seven decades. National leaders, people marching in the street and people of quiet resolve, bureaucrats, teachers, renowned physicists, religious leaders, non-governmental experts and countless others have worked their tails off to prevent mushroom clouds. They have known at the cellular level what advocates of tailored nuclear deterrence refuse to acknowledge: The most important threshold in warfare isn’t the yield of a nuclear weapon; it’s the first use of a nuclear weapon in seven decades — regardless of yield.

Michael Krepon is Co-Founder of the Stimson Center. This piece originally ran in Arms Control Wonk on March 19, 2017.

Subscription Options

* indicates required

Research Areas

Pivotal Places

Publications & Project Lists

38 North: News and Analysis on North Korea