So, while the US investment in ballistic missile defense motivates this panoply of new weapons, it provides no significant additional security against Russian attack. This is reminiscent of how President Reagan’s attachment to ballistic missile defense, aka the Strategic Defense Initiative (SDI) or Star Wars, derailed the opportunity at the Reykjavik summit in 1986 for a world-changing agreement with Secretary General Gorbachev on the elimination of nuclear weapons.

The bilateral reduction option takes away the need for a launch-under-attack posture for both the United States and Russia and reduces both deployed arsenals by about one quarter. Publicly available estimates[6],[7] suggest[8] that the number of Russian silo-based warheads is about equal to the US value of 400, so that the warhead-count reductions required to eliminate silo-based ICBMs would be similar on both sides. As discussed above, however, it should be anticipated that Russia would insist on verifiable limits on US ballistic missile defense capabilities, since reducing warhead and/or penetration aid count disadvantages the party with weaker ballistic missile defenses.

The most stabilizing nuclear declaratory policy would flow from the verified elimination of nuclear weapons, consistent with the Treaty on the Prohibition of Nuclear Weapons. If there are no nuclear weapons, there can be no nuclear war. This would be a welcome but highly unlikely outcome of bilateral dialogue with Russia. Russia considers itself to be confronted by superior conventional NATO forces and has made clear that it considers that nuclear forces may be necessary for its defense against conventional attack.

Current Russian policy[10] states that the “[t]he Russian Federation reserves the right to use nuclear weapons in response to the use of nuclear and other types of weapons of mass destruction against it and/or its allies, as well as in the event of aggression against the Russian Federation with the use of conventional weapons when the very existence of the state is in jeopardy.” The policy specifies the conditions under which it is possible that Russia would use nuclear weapons:

The second most stabilizing nuclear declaratory policy is one of “no first use.” If no one uses nuclear arms first, again there can be no nuclear war. But for the same reason as above this is not a likely outcome of bilateral dialogue with Russia. On the other hand, in parallel with the bilateral dialogue with Russia, the United States should initiate serious discussions with its allies and partners as to whether they would realistically want the United States to use nuclear weapons to defend them against conventional attack, rather than act solely as a deterrent to nuclear use against them. First nuclear use by the United States could subject these nations to devasting nuclear counterattack, likely far worse in consequence than a protracted conventional war, even one that began with an initial successful conventional military invasion. The confidence of our allies and partners in our support has been shaken in recent years and may take some time to first re-establish and then strengthen, but just the fact that this will be a difficult task is no justification for shirking it.

The United States and Russia might be able to agree in the near term on a policy that nuclear weapons would only be used as a measure of “defensive last resort.” This concept was first put forward by McGeorge Bundy, William J. Crowe Jr. and Sidney Drell[11] in 1993, and has been re-iterated by this author[12] and by Perkovich and Vaddi[13] in closely related forms. In effect, this policy would state that, “We would only consider the use of nuclear weapons to defend our states, and our allies and partners, against imminent existential threat from nuclear-armed adversaries, and then only once all other means had been exhausted.” This is close to recent published US[14] and Russian nuclear declaratory policy noted above, but simpler and arguably clearer in intent and more restrictive. Surprisingly, in one way this is stronger than “no first use,” in that a nuclear response to a non-existential nuclear attack that could be countered by conventional means would not be considered.

“I’m not going to tell you what our declaratory policy is and how much it will change, because ultimately that’s a decision the president will make, and the president hasn’t made that decision. … I think that we can all agree that nuclear weapons are a credible deterrent against existential threats. But I think people of big intellects and good faith can disagree about how explicit or ambiguous we should be about scenarios under which we might consider the use of nuclear weapons below that threshold. And that is a debate that we will have internally.”

This and the Russian posture make it clear that moving to a nuclear declaratory policy in which nuclear weapons would only be considered for use as a defensive last resort against an imminent existential threat from nuclear-armed adversaries would be a significant step for either side. But perhaps such a step would not be impossible to take—particularly on a bilateral basis. If this could be achieved, it would constitute a significant advance. 

In sum. The world is at a fork in the road. One path forward leads to a safer world, potentially free of nuclear weapons, while the other leads to rapidly increasing risk of nuclear annhilation. Bilateral strategic stability dialogue is a promising means to choose the safer path. Success will require the participants in these dialogues to view themselves as sitting on the same side of the table, trying to solve together the problem of reducing the vast nuclear threat to all humanity.

[5] H.M. Kristensen and M. Korda, “United States nuclear weapons, 2021” Bulletin of the Atomic Scientists, 2021, Vol. 77, No. 1, 43-63

[6] H.M. Kristensen and M. Korda, “Russian nuclear weapons, 2021,” Bulletin of the Atomic Scientists, 2021, Vol. 77, No. 2, 90-108

What a paltry proposal from the nuclear weapons establishment, now writing for the Bulletin of Atomic Scientists. With a new treaty signed and ratified for the Prohibition of Nuclear Weapons which finally banned the bomb and closed the legal gap in the old Non-Proliferation Treaty which merely called for “good faith” efforts for nuclear disarmament, asking now for certain missile controls, etc. is ridiculous. The world is facing catastrophic climate destruction and with 14,000 nuclear bombs on the planet, thousands of them primed and ready to shoot in minutes, and the US planning to spend over a trillion dollars in… Read more »