The Doctrine is still being revised. The latest version available online is a PDF document from March 2005, and nukestrat.com provides a preliminary analysis of its contents. The doctrine emphasizes several times that the United States is legally permitted to use nuclear weapons:
The United States and its allies articulated their abhorrence of unrestricted warfare by codifying “laws of war,” and turning to definitions of “just war.” The tremendous destructive capability of WMD and the consequences of their use resulted in a number of agreements restricting deployment and use. Nevertheless, while the belligerent that initiates nuclear warfare may find itself the target of world condemnation, no customary or conventional international law prohibits nations from employing nuclear weapons in armed conflict. (page 10, emphasis in original)One of the reasons cited for the necessity of nuclear operations is weapons proliferation.
Future adversaries may conclude they cannot defeat US military forces and thus, if they choose war, may reason their only chance of victory is through WMD use.As the Australian Herald Sun points out, "Several scenarios allow nuclear strikes without enemy WMD in the equation."
Military forces must prepare to counter weapons and capabilities that exist or will exist in the near term even if no immediate likely scenarios for war are at hand. To maximize deterrence of WMD use, it is essential US forces prepare to use nuclear weapons effectively and that US forces are determined to employ nuclear weapons if necessary to prevent or retaliate against WMD use. (page 46)
Geographic combatant commanders may request Presidential approval for use of nuclear weapons for a variety of conditions. Examples include:
(page 47, emphasis mine)
- An adversary using or intending to use WMD against US, multinational, or alliance forces or civilian populations.
- Imminent attack from adversary biological weapons that only effects from nuclear weapons can safely destroy.
- Attacks on adversary installations including WMD, deep, hardened bunkers containing chemical or biological weapons or the C2 infrastructure required for the adversary to execute a WMD attack against the United States or its friends and allies.
- To counter potentially overwhelming adversary conventional forces, including mobile and area targets (troop concentration).
- For rapid and favorable war termination on US terms.
- To ensure success of US and multinational operations.
- To demonstrate US intent and capability to use nuclear weapons to deter adversary use of WMD.
- To respond to adversary-supplied WMD use by surrogates against US and multinational forces or civilian populations.
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My opinions follow.
To me, reasons (e) and (f) seem vague enough to invoke pretty much at any time. I find it ironic that weapons proliferation is a key reason cited for readiness and deployment of nuclear weapons — that would seem to be a good argument for spending more effort on controlling, recovering, and reducing stockpiles of nuclear material, not proliferating them further.
I also think it's interesting that the document meticulously avoids using the acronym "WMD" to describe United States weapons, even though nuclear weapons are "weapons of mass destruction" by any definition. WMD are always used by an adversary. I suspect replacing every instance of "nuclear weapons" or "nuclear" with "WMD" in this document would give it a rather different flavour and perhaps expose some absurdity.
So i tried the experiment. Here's the original document converted to HTML by Google (Google seems to cut it off after 42 pages). Here's the same document with "WMD" substituted for "nuclear". As an example, the summary of revisions now says:
- Contains discussion of both strategic and theater and WMD operations
- Covers the purpose of United States WMD forces
- Revises the discussion of WMD use across the range of military operations
- Provides an updated and expanded discussion of WMD operations
- Introduces the joint targeting cycle process to WMD operations
- Updates employment and force integration considerations
- Adds an entire chapter on theater WMD operations