Recent news that President Obama may be considering changes in nuclear deterrence policy has caused a storm of speculation as to whether the time is right for the U.S. government to declare a no first-use policy. In short, this refers to a policy by a state that possesses nuclear weapons not to use them as a means of warfare unless first attacked by an adversary with nuclear weapons. The United States has never had a no first-use policy, preferring the concept of strategic or calculated ambiguity to suggest that it could respond to a crisis with nuclear weapons, if appropriate, or with the massive use of conventional weapons. Thomas Schelling, who called deterrence “the diplomacy of violence,” reminds us that latent violence may influence a state’s choice and that the threat of more damage to come can make a state yield or comply. One of the rationales for retaining nuclear weapons is to deter an adversarial nation from initiating a conventional war and using its nuclear weapons as a latent threat against U.S. military actions. As a matter of extended deterrence, allies such as Japan and South Korea would like to be assured that the United States will not hesitate to use all means to protect them, given that they have committed to not developing nuclear weapons (per the Nuclear Nonproliferation Treaty).

Writing at War on the Rocks, Daryl Kimball of the Arms Control Association believes it is time for the United States to take the pledge of no first-use of nuclear weapons, calling a first-use policy part of “dangerous, Cold War-era nuclear thinking” that could lead to early use of nuclear weapons by adversaries such as Russia or China. He decries the possible scenario of “launch under attack” – e.g., a massive U.S. nuclear weapons launch in response to early satellite warnings of an adversarial missile launch – as something that increases the risk of catastrophic accidents or miscalculation between states. While the U.S. military has a “launch under attack” capability, the U.S. government does not have a written policy to “launch on attack” or “launch on warning.” The option is available to the president if he chooses to use it, again under the principle of strategic ambiguity. Since at least 1997, if not earlier, the tendency of U.S. presidents has been to increase the time to make any decision to respond to an attack with nuclear weapons. The president always has the option to not order an attack upon receiving confirmation that another nuclear power is attacking the United States with strategic nuclear forces. U.S. nuclear forces are not on “hair triggers” — evoking an image of Colt pistols set for release at the slightest pressure — that would lead to an accidental launch during an international crisis.

Kimball apparently does not believe that the United States should consider first-use of nuclear weapons in response to non-nuclear military combat operations due to the risk of potential escalation to uncontrolled nuclear weapons use by both sides. Despite the recent NATO Warsaw summit in which the alliance declared the intent to retain nuclear arsenals, Kimball believes that U.S. allies only require conventional forces to deter a non-nuclear threat from Russia or China or North Korea. Recent Russian threats to use tactical nuclear weapons, or “escalating to de-escalate,” prove him wrong. Similarly, China’s no first-use policy may not hold if a U.S. military strike with conventional weapons were to take out key command and control nodes necessary for China’s nuclear deterrent to remain credible. With respect to North Korea, current U.S. nuclear weapons policy allows for first use of nuclear weapons in retaliation against chemical or biological weapons use, or to deter a massive conventional attack against South Korea. These examples illustrate the need to offer the president the option of pre-empting an adversary’s nuclear or non-nuclear attack with nuclear weapons, if the stakes are high enough.

This debate about U.S. nuclear policy is not new and has not been advanced by Kimball’s arguments. Michael Gerson argued in 2010 that the U.S. government had missed an opportunity to adopt no first-use in the last Nuclear Posture Review. On the other hand, political and military advisors prefer to leave the president with options for different scenarios, such as responding to unambiguous intelligence warnings that a nuclear-armed state is preparing to attack the United States with its nuclear arsenal.

However, we believe that Kimball’s discussion is not so much about whether the United States is willing to use nuclear weapons first. Rather, Kimball seems to want the U.S. nuclear weapons arsenal taken off alert. He uses a quote from the Global Zero report on nuclear risk reduction that “U.S. land- and sea-based strategic forces, armed with nearly 1,000 warheads, stand ready for immediate firing in peacetime.” Global Zero uses this statement to discuss how the United States could stand down its readiness for immediate launch and instead, adopt a practice of moving bombers, land-based nuclear missiles, and nuclear-armed submarines to high-alert during crises. This might reduce the risk of accidents or misunderstandings leading to nuclear war. Under the Global Zero construct, adopting a no first-use policy would logically lead to de-alerting as a next step. This approach has some significant problems, were it to be adopted.

First of all, we should stop believing that nuclear deterrence is Cold War thinking by people who want to retain Cold War weapon systems. The United States retains aircraft carriers, heavily armored tanks, and high-performance aircraft that were designed during the Cold War because they have a demonstrated role in contemporary scenarios. Similarly, because adversary nuclear weapons still exist as an existential threat today, the readiness of U.S. nuclear weapons has a place in current national security discussions. As Secretary of Defense Ash Carter noted in congressional testimony, nuclear weapons are the bedrock of our security. We want the leaders of Russia, China, and other states to hesitate before attacking the United States because they know the United States has more than 1,000 nuclear weapons ready to launch on the president’s order. This does not mean that the president would direct a nuclear first-strike, but strategic stability is maintained because of the high-alert status of land- and sea-based nuclear missiles.

Second, if the United States were to de-alert its nuclear forces, what message would re-alerting them send to an adversary during a crisis situation? This point was studied during the 2010 Nuclear Posture Review, and the analysis suggested that (assuming both sides had “de-alerted” their nuclear forces) a race by the two sides to regain a high-alert posture might be misinterpreted and lead one to attempt a pre-emptive strike on the other. De-alerting U.S. nuclear forces has far more peril than promise in future conflict scenarios.

The question of whether the U.S. government should change its policy about attacking a non-nuclear state that employs chemical or biological weapons against U.S. forces or allies is a different issue. This is (perhaps) a genuine example of Cold War thinking; that an adversary might use chemical or biological weapons to such a devastating effect that the use of nuclear weapons in retaliation would be seen as proportional. It is hard to believe that there would be a scenario today in which the U.S. government would respond to a nation-state’s chemical or biological weapons attack with nuclear weapons, but the interjection of the possibility of an “irrational response” may deter such an attack in the first place. Indeed, that is part of the calculus of strategic ambiguity and illustrates its value, which is evident in that it provides additional options for response. This is a political decision, whether the United States should rely solely on superior conventional forces to retaliate against chemical or biological weapons attacks.

It is natural for President Obama to be reflective about the role of nuclear weapons employment, and he has certainly engendered a lively discussion on the topic during his two terms in office. However, it would be surprising and ill-advised if, in the last year of his administration, he made such a radical deviation in U.S. nuclear weapons employment policy by issuing a no first-use doctrine. Certainly this issue should be discussed in the development of the next administration’s nuclear weapons employment policy, and without a doubt, these same arguments will resurface. The next administration will have to consider whether nuclear weapons are meant solely to deter the adversarial use of nuclear weapons — to include a nuclear-induced electro-magnetic pulse attack. Until then, there is strong and compelling evidence that current doctrine works. The United States should retain its “ace in the hole” — the threat of first-use of nuclear weapons — as it anticipates future crises that will surely emerge.

Al Mauroni is the Director of the U.S. Air Force Center for Unconventional Weapons Studies. David S. Jonas is a partner at FH+H firm, a DC area national security law firm. He is also an adjunct professor at Georgetown and George Washington University Law Schools where he teaches nuclear nonproliferation law and policy. The opinions, conclusions, and recommendations expressed or implied are solely those of the authors and do not necessarily reflect the views of the Air University, U.S. Air Force, Department of Defense, or the FH+H law firm.

Image: U.S. Air Force, Michael Peterson

Correction: This article originally stated that the United States has not had a “launch under attack” policy since at least 1997. This was not entirely accurate and that sentence has been replaced with a more nuanced explanation.