The Defense Department released a Law of War Manual in June that says some interesting things about how the United States views legal questions about the use of nuclear weapon.
Legal perspectives are terribly important in the United States. I observe that the United States tends to think about nuclear weapons in a far more legalistic manner than other states, whether friend or foe. I was in one meeting where an American participant talked about the legal constraints on a President contemplating the use of nuclear weapons when a French colleague laughed. ”We would throw the lawyers out the room!” he said. That struck me, since of course in the United States that would mean the President would have to throw himself out of the room.
For the past couple of years I’ve been working on a big idea that looks at how the United States might alter its approach to nuclear deterrence, one that is rooted in legal questions about military necessity and the use of nuclear weapons. But I am getting ahead of myself! There is still the issue of the June 2015 Law of War Manual.
Nuclear Weapons and the Law of War Manual in Six Points
Heather Williams, King’s College London
While we were all distracted by the Iran deal (see last nine ACW posts), the US Department of Defense released its Law of War Manual back on June 12, 2015. Heavily footnoted legalese may not seem quite as gripping as the down-to-the-wire drama of negotiations in Vienna, but there are some good nuggets in there with respect to the legality of nuclear weapons use and nuclear deterrence. This comes after a controversial NPT Review Conference in May, and legal justification for nuclear weapons runs up against increasing pressure from some states in the humanitarian impacts initiative for a nuclear weapons ban.
Much of the Manual is based on the 1977 Additional Protocol I (AP I) to the Geneva Conventions (not to be confused with the IAEA Additional Protocol); however, the United States never signed up to AP I, nor does AP I apply to nuclear weapons. At first glance, the Manual only devotes two pages and 373 words to nuclear weapons. But did I mention the footnotes? Those two pages contain an additional 1034 words in the footnotes, but, more importantly, the 1996 ICJ Advisory Opinion is heavily featured throughout the entire Manual.
Here are some highlights:
1. Non-nuclear weapon states cannot impose customary international law when it comes to nuclear weapons. Interests of nuclear armed states take precedent because they are “specially affected.” A footnote on page 32 cites the ICJ Opinion: “Evidence of a customary norm requires indication of ‘extensive and virtually uniform’ State practice, including States whose interests are ‘specially affected.’ … With respect to the use of nuclear weapons, customary law could not be created over the objection of the nuclear-weapon States, which are the States whose interests are most specially affected.”
2. Non-use of nuclear weapons does not translate into customary international law. This is because lack of use is not the result of a legal opinion or ruling, and, to cite the 1996 ICJ Opinion, “if nuclear weapons have not been used since 1945, it is not on account of an existing or nascent custom but merely because circumstances that might justify their use have fortunately not arisen.”
3. As long as nuclear weapons exist their use would be “authorize-able”, or justifiable, unless there was a legal prohibition with the support of nuclear-armed states (see point 1): “Like other aspects of the law of war, the rules relating to weapons are generally characterized as prohibitive law forbidding certain weapons or the use of weapons in certain instances rather than positive law authorizing the weapon or its use. The lawfulness of the use of a type of weapon does not depend on the presence or absence of authorization, but, on the contrary, on whether the weapon is prohibited.”
4. Nuclear weapons use would not necessarily be disproportionate. This is where things get interesting because it is talking about specific conditions of use, rather than nuclear weapons in the abstract. As part of the ICJ case, the United States submitted a statement, which is cited on page 314: “Whether an attack with nuclear weapons would be disproportionate depends entirely on the circumstances, including the nature of the enemy threat, the importance of destroying the objective, the character, size and likely effects of the device, and the magnitude of the risk to civilians. Nuclear weapons are not inherently disproportionate.” If nuclear weapons were used in response to a nuclear attack, for example, that would be proportionate, assuming similar yields and targets.
5. Nuclear weapons use would not be illegal based solely on the humanitarian and environmental effects. International law prohibits “asphyxiating, poisonous, or other gases, and all analogous liquids, materials, or devices’. However, if these effects are a by-product rather than the primary intent of a weapon, that weapon could still be considered legal: “the rule is understood only to prohibit weapons whose prime, or even exclusive, effect is to poison or asphyxiate. Thus, for example, smoke, flame, napalm, conventional explosives, and nuclear weapons are not covered by this rule, even though these weapons may produce asphyxiating or poisonous by-products.” These humanitarian and environmental effects should not be ignored, but rather consideration should be given to the specifics of potential use and how to minimize collateral damage in the extreme conditions when nuclear weapons would be used.
6. Nuclear weapons use would not necessarily be indiscriminate, another contention of just war proponents: “There is no general prohibition in treaty or customary international law on the use of nuclear weapons…. nuclear weapons must be directed against military objectives. In addition, attacks using nuclear weapons must not be conducted when the expected incidental harm to civilians is excessive compared to the military advantage expected to be gained.” Again, this raises more interesting questions about targeting and whether or not lower-yield nuclear weapons would be more humane.
Still with me? If so, let’s talk about what is not in the Manual, namely a discussion of arms control treaty obligations- a rather strange omission for a document on international law. The Manual acknowledges US non-proliferation responsibilities, along with agreements to reciprocally reduce its arsenal, but on p. 394 it says, “Some of these agreements may not apply in times of war. Guidance on nuclear arms control agreements is beyond the scope of this manual.” Fair enough, but then p. 925 engages in a discussion about the specifics of the Outer Space Treaty so it seems like an attempt to deflect difficult questions about disarmament. On that note, most noticeably absent is any mention of US commitments to “general and complete disarmament” under Article VI of the NPT. One possible explanation for this is that the Manual is about the laws of war rather than treaty law, which could be discarded in times of war and “supreme national interest”- a fine line, indeed.
Proponents of a nuclear weapons ban are likely to pick up on the following point on p. 72: “Certain prohibitions and certain other rules in the law of war that reflect customary international law have been described as reflecting ‘elementary considerations of humanity.’ These ‘elementary considerations of humanity have been understood to be ‘even more exacting in peace than in war.’ Thus, these legal standards, at a minimum, must be adhered to in all circumstances.” And herein lies the heart of the debate between nuclear deterrence, which requires a credible threat of use of nuclear weapons, and humanitarian approaches to war. Ideally, the humanitarian impacts initiative would provide a forum for diverse discussion of these issues and seize the opportunity provided by the release of the Law of War Manual.