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No Launch on Warning

NOTE: The term “Launch on Warning” (L-o-W) is used here in reference to retaliation with rocket-mounted nuclear weapons to a perceived nuclear attack in response to a warning (by radar or satellite sensors) of attacking missiles, before any incoming warhead had arrived and detonated. In the U.S. military dictionary the term “Launch under Attack” (LUA) has the equivalent definition. “Launch on Warning” is not defined in the web version of the dictionary, but we understand it is used to include a pre-emptive strike, if the enemy is perceived to be preparing for nuclear war.


Prevention of nuclear war between Russia and the U.S. is vital for the future of the world because both countries retain such large arsenals that if they should go to war the result would be much more extensive than complete destruction of both countries. Radioactivity, and smoke from the many firestorms, would severely affect at least the whole of the northern hemisphere. Nuclear winter, widespread starvation, and other consequences might even combine to exterminate the human species. In the present relationship between the U.S. and Russia an intentionally started nuclear war is extremely improbable. There is, however, the risk of an unintended war starting from one cause or another, and under the policy of L-o-W the likeliest cause is a false warning. To risk such a disaster happening because of a mere accident to a man-made system is absurd.

While the claim that long-term stability can be assured through nuclear deterrence must be rejected, deterrence remains the central basis upon which arms control discussions, and agreements, between the governments and military establishments of the U.S. and Russia take place. Deterrence is in theory achieved when a potential attacker is convinced that an attack will be unavoidably followed by retaliation so devastating that it would be irrational to attack in the first place. Nuclear deterrence is assumed for the present discussion because the focus here is on changing just one feature in the two States’ military posture. It is argued that the change to a policy of “NO L-o-W” is a logical necessity and is readily possible; it is urgently needed, and it does not require any immediate change in the assumptions upon which current policy is based, whether these are valid or not.

The Emergence of a Launch on Warning Policy

As the accuracy of nuclear weapons advanced, it was realized that a massive pre-emptive salvo directed at command and control systems and retaliatory weapons could diminish or eliminate a capacity to retaliate. If either side believed it could achieve such a “disarming first strike”, it might be tempted to attack. To avoid this weakening of deterrence through the pre-emptive destruction of an adversary’s retaliatory forces, both sides explored the possibility of launching retaliation before the first impact – thus “Launch on Warning”.

During atmospheric testing of nuclear weapons in the early 1950’s the phenomenon called “Electro-Magnetic Pulse” (EMP) was discovered. EMP is an extremely sharp and energetic electromagnetic impulse that is emitted by electrons traveling at nearly the speed of light from a nuclear explosion. It disrupts unshielded electrical and electronic equipment over a wide area. This possibility that electrical disruptions might prevent retaliation provided a second reason to adopt L-o-W.

It is probable that by 1969 L-o-W was the military policy on both sides, and had been for a number of years. The recollections of former officers and enlisted men of Strategic Air Command (SAC) from the early 1970’s confirm that L-o-W was in effect then. The capability, and presumably the policy, of L-o-W are retained by the U.S. and Russia, even though the Cold War is regarded as over. This seems inexcusably dangerous.

The Danger of Inadvertent Nuclear War from False Warnings or Chance Coincidences

Launch on Warning has kept the world exposed, for at least 30 years, to the danger of a nuclear war caused by nothing but a coincidence of radar, sensor, or computer glitches, and a temporary failure of human alertness to appreciate that an unexpected message of attack from the warning system is false, the enemy having done nothing.

During the Cold War, many mishaps within the nuclear retaliation system on the U.S. side are known to have occurred, including false warnings [See Alan F. Phillips, “20 Mishaps that Might Have Started Accidental Nuclear War”]. There must have also been many similar incidents on the Russian side. One has been reported in which a Russian officer decided on his own initiative not to report an apparently grave warning on his computer screen, in the correct belief that it was a false warning. He may have saved the world, but was disgraced for failing to follow his orders; his career was ruined, and he suffered a mental breakdown.

On the morning of November 9th 1979, a war games tape was running on a reserve computer when failure of the operational computer automatically switched in the reserve. The Threat Conference saw the picture of a massive attack in a realistic trajectory from Russian launch sites. On that occasion, preparation to retaliate got as far as launch of the president’s National Emergency Airborne Command Post before the error was discovered.

Exploring the NO L-o-W Posture

To change from L-o-W to NO L-o-W does not require any change of alert status of the retaliatory system. It only requires a change of standing orders and standard operating procedure, such that no launch may take place until a nuclear detonation is reported. Furthermore, the elimination of L-o-W does not eliminate any other retaliation options. It just ensures that retaliation would not take place without confirmation of a nuclear detonation. If, and only if, indication of a nuclear explosion was received at the predicted arrival time of the attack, the final order to launch could be sent immediately to the silos. The actual retaliatory launch could probably take place within a minute of the first detonation. If the final order to launch was not received within a certain short time after the time of predicted impact, the launch preparations would be reversed.

A policy of NO L-o-W would not eliminate the horrific threat of nuclear annihilation; only the abolition of nuclear weapons can do that. But a NO L-o-W posture would remove the danger of launching nuclear-armed rockets in response to a false warning. That would probably eliminate 90% of the current risk of nuclear war between the U.S. and Russia. If only one side changes to NO- L-o-W, the risk of a purely accidental war from a false warning is approximately halved, immediately.

The Effect on Deterrence

One possible objection to NO L-o-W is that it might impair deterrence and tempt one side to try a “disarming first strike”. There are good reasons why this objection should not be allowed to prevent the policy change. For either side to consider first strike to be a rational option, the attacking side would have to be absolutely sure that its first salvo would fully disarm the other’s retaliatory capacity. They would know that any surviving weapons would pose a retaliatory threat that could be launched immediately after the first bomb had detonated. Under NO L-o-W the degree of alertness of surviving weapons would not be reduced, and retaliation for a real attack would still be launched promptly.

The other possible way to achieve a successful disarming first strike would be a first salvo engineered to maximize Electro-Magnetic Pulse. It is hardly credible that the attacking side could feel sure that their EMP would disrupt communication and launch mechanisms sufficiently, since they would know that military electronics will have been shielded. Furthermore, they would know that submarine-launched missiles would not be disabled, because the sea-water shields submarines and their contents. The side planning a pre-emptive attack would also have to be sure that its adversary had in fact changed to and remained under a policy of No L-o-W. They cannot be sure of this without verification. So from the point of view of preserving deterrence, verification is actually undesirable.

Thus, a NO L-o-W policy on either side would have minimal impact on deterrence, and would be an advantage to both, simply because it halves the risk of a purely accidental nuclear war. NO L-o-W by both sides makes this particular risk zero. Neither side wants an accidental war. They know that if either side mistakenly launches nuclear weapons both countries are going to be destroyed: it makes no difference who started it. If, despite these arguments, the military establishment on either side is not persuaded to abandon L-o-W, the head of state must balance the elimination of the very definite risk of accidental war due to a false warning, against a hypothetical possibility of weakened deterrence resulting in war. The results of a nuclear war would be the same, whether started by accident or by intention.


For the present, adoption of a NO L-o-W policy offers a quick and simple means of reducing the danger of accidental war. All the world’s people would be safer for the change. Therefore all governments have a duty to their people to urge the U.S. and Russian governments to make it at once.

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