U.S. Nuclear Force Posture and De-Alerting

Fact Sheet
Bureau of Arms Control, Verification, and Compliance
December 14, 2015


We posture our nuclear forces to maintain strategic stability day-to-day and in crisis, deter attacks on the United States and our allies, and prevent unauthorized or accidental launch of U.S. nuclear forces.

The Facts about the Readiness of U.S. Nuclear Forces.

  • Since the end of the Cold War, our strategic bomber forces and non-strategic nuclear forces have been de-alerted. They are not loaded with nuclear weapons day-to-day.
  • We maintain a portion of our ballistic missile submarine force at sea day-to-day. This is to ensure their survivability.
  • We maintain the bulk of our ICBM force on alert day-to-day.
  • The readiness and survivability of our bomber, submarine, and non-strategic nuclear forces can be increased in a crisis or conflict at the direction of the President.
  • All of our ballistic missiles are targeted on open ocean areas day-today to ensure that in the very unlikely event of an accidental launch they could not and would not strike another nation.

U.S. Nuclear Forces are not on Hair-Trigger Alert. A hair trigger is deliberately calibrated to fire a weapon with only the slightest pressure applied to the trigger. This is not an accurate description of U.S. nuclear forces. U.S. “alert” posture simply means a portion of our forces (those on “alert”) are ready to launch upon receipt of an authenticated, encrypted, and securely transmitted order from the President of the United States.

  • We have multiple redundant technical and procedural measures in place to prevent unauthorized or accidental launch. A carefully designed combination of technical and procedural measures ensures only the President of the United States can authorize the use of U.S. nuclear weapons.
  • We also operate an extensive early warning and attack assessment system of satellites, radars, and command centers that ensures we can detect an attack on the United States or our allies and provide the President with an accurate assessment of the origin and interne of that attack in a timely way. We have a set of standard operating procedures that govern how we vet and convey warning and attack assessment information to the President. The purpose of this system and procedures it to enable the President to make a deliberate decision based on accurate information; the purpose is NOT to seek permission to launch from the President.
  • There is no delegation of the Presidential nuclear use authority to the U.S. military or to automated systems.

Further De-alerting Would be Destabilizing in a Crisis. During our 2010 Nuclear Posture Review we studied in detail whether we should de-alert further any portion of our nuclear forces.

That analysis took into account the impact further de-alerting would have on strategic stability and deterrence day-to-day, and in crisis or conflict. Our analysis found that further de-altering would be very difficult to verify; even if verifiable, further de-alerting would be destabilizing in a crisis as sides raced to “re-alert.”

  • Because we assessed that the likelihood of a surprise attack day-today is remote, further de-alerting will not improve strategic stability in the day-to-day scenario. Neither the United States nor Russia poses a disarming first strike capability against the other in our respective day-to-day postures. Thus, de-alerting would not enhance strategic stability because there is no incentive to launch a surprise attack for either side.
  • However, our assessment of the impact of further de-alerting on strategic stability in crisis led us to the conclusion that further de-alerting would be destabilizing, not stabilizing. Countries with de-alerted nuclear forces would face intense pressure to re-alert those forces in a crisis with a nuclear armed adversary. Doing so could incentivize an adversary to strike before the other side’s forces was once again operational.
  • Put another way, further de-alerting addresses the least dangerous time period regarding strategic stability: the day-today environment when war is not imminent, and it risks undermining strategic stability in crisis, making war more likely.
  • Our conclusion was that improved command and control systems and processes are a better method of improving strategic stability than de-alerting, and we are doing just that.

The United States Does not have a Launch on Warning Doctrine. President Obama’s Nuclear Employment Strategy directed DoD to retain the option for the President of launching ICBMs under attack while ensuring that we are not reliant on launch under attack to meet our requirements. A launch under attack option is not the same as a launch on warning doctrine. There are two fundamental differences.

  • First, a launch under attack decisions is not based solely on a single warning indicator. It is informed by an attack assessment that considers and confirms warning information from multiple, independent sensors. An attack assessment also considers the apparent intent of the incoming attack in the context of the international situation.
  • Second, the President does not have to launch under attack. Our current day-to-day posture ensures the President does not face a “use it or lose it” situation, which he could if our forces were de-alerted. Our command and control system and submarines at sea would survive a surprise attack and enable a devastating response. The decision to launch under attack is a choice, not an imperative.

De-alerting would not Increase Presidential Decision Time. It is true that if our attack assessment indicates a large scale attack on U.S. nuclear forces the President would have less than 30 minutes in which to make a decision to launch our ICBMs under attack or not. However, time is not determined by our force posture, but rather the promptness of the weapons system employed by the adversary. Therefore, de-alerting doesn’t create more time to decide, it eliminates it.

We are addressing the Cyber Threat. The most likely cyber threat to nuclear weapons systems would come from adversary states trying to prevent a launch rather than cause one. That said, we are paying extremely close attention to potential cyber threats to our warning, attack assessment, and command and control capabilities. There are multiple physical and procedural barriers to an attempt to inject false warning information or a launch order into our forces through cyberspace.

  • All the coded information required to unlock, enable and launch a nuclear-armed ballistic missile is not physically available in the ICBM launch control facilities or on the ballistic missile submarines.
  • Those codes must be received from elsewhere, and authenticated as authorized by the President by multiple personnel. Key codes that are required to enable a launch do not reside on any computer network. They exist only in hard copy.