Chapter 22 builds on its preceding chapter, discussing “security detention,” confinement without criminal charges for security reasons during armed conflicts or other situations of violence. This is presumably the fate of most, if not all, of the forty remaining Guantánamo detainees. The chapter compares security detention with other forms of wartime internment, including World War II Swiss internment of US and German aircrews. Law, LOAC or otherwise, authorizing internment during non-international armed conflicts is sparse but authorities (such as this textbook) point to a 2014 UK case, and the criticism that followed its resolution, as pointing the way to LOAC (Sections III and IV of 1949 Geneva Convention IV) that would allow and control security detention. Much of the chapter describes present-day US security detention policy. A difficulty is squaring LOAC with security detention beyond the conclusion of hostilities. Surprisingly, however, the US Supreme Court has a lon, if not unanimous, record of approving security detention well past the end of hostilities. Those cases suggest that current Guantánamo detainees are probably going to age and die in place.

Chapter 14 describes lawful human targets, the first being enemy combatants. Their required characteristics, activities, and locations are covered, followed by exceptions to their lawful targeting: prisoners, those showing intent to surrender, and those incapacitated by wounds. Wrongful use of force investigations are detailed, to impress the fact that violations of an exempt targeting status have consequences within our own armed forces. What legal standard is applied to the shooter when investigating possible unlawful use of force? Lawful civilian targets are considered, as well: when one is targeted he may return fire on civilians in self-defense; and when civilians are directly participating in hostilities (DPH), as is often the case in recent conflicts. Significant space is devoted to explaining what constitutes DPH, as well as to continuous combat function, the higher form of DPH. Targeting of heads of state (e.g., Saddam Hussein, Adolf Hitler, the US president) is covered. Then, is there a duty to capture, rather than wound? To wound, rather than kill? Finally, the politically fraught killings of Iranian General Suliemoni and Anwar al-Aulaqi are examined for LOAC compliance.

Chapter 18 attempts to make cultural property attractive to LOAC students. Destruction and pillage of cultural property have been a wartime problem for hundreds of years. The 1954 Hague Convention protecting cultural property is one of the more significant treaties combatants should be aware of, regardless of the blandness of the topic to many warfighters, because it is a potential fast-track to trial. The 1954 Convention and its first Protocol (of two) were issued on the same day, reflecting ineptitude in their drafting. Nevertheless, the Convention’s pertinent articles and its sometimes-unique terminology are discussed. It is the second Protocol (1999) that gives clarity and precision to the Convention, which is closely examined. Several fictional scenarios are employed to make clear the Convention’s workings. Its relationship to the 1977 Additional Protocols is strong, as is shown. The Cases and Materials examine two prosecutions arising from the conflict in the former Yugoslavia that demonstrate that the Convention has teeth that bite combatants who disregard its prohibitions.

Chapter 16 shows torture to be a lose-lose practice, its results virtually always unreliable. It is shown to be contrary to customary international law, the domestic and military laws of virtually every state, as well as the Geneva Conventions, the Rome Statute of the International Criminal Court and, of course, LOAC. Yet torture persists. After describing torture, international examples are detailed, including from CIA black sites. Excuses for torture are given and rebutted. Particular attention is given to US uses of torture after 9/11, none of which has been shown to have been useful, contrary to presidential assertions. Israel’s torture experience is covered, as is the French experience in Algeria. Waterboarding is clearly identified as torture, with several examples provided. The “ticking time bomb” scenario is argued to be an intellectual fraud, despite its being a frequent excuse for both liberals and conservatives to promote it. US military practice is also detailed. Cases and Materials include a real-world Sri Lankan ticking time bomb experience and a copy of a chilling US Department of Justice memorandum describing – and authorizing! – CIA black site methods of torture.

Chapter 21 addresses military commissions. Their history and evolution are described. During the Mexican-American War, they were a modest military law stopgap in foreign countries. The US Civil War and the Lieber Code (Chapter 2) made them what they are today: rough-edged military field tribunals to address the war crimes of foreign combatants. Their value was proved following World War II, when all the Allied states employed them. Guantánamo’s post-9/11 perverted version of military commissions, in the shadow of CIA black sites and “enhanced interrogations,” may have ended their utility: initiated by civilian political appointees with the aim of denying prisoners not just POW status but basic human rights and legal protections, Guantánamo’s military commissions have been an abject failure, brought to heel by civilian courts’ legal resistance and forced recognition of civilian legal oversight. Guantánamo’s record of eight convictions in eighteen years, three of which have been vacated, is proof of their legal ineffectiveness and moral hollowness.

Chapter 7 discusses LOAC’s core principles. This text holds that there are four core principles, per the International Court of Justice. Distinction requires that Parties to a conflict always distinguish between civilians and civilian objects and combatants, and fire only on military objectives. Military necessity, the second principle, is very elastic, holding that all lawful measures to defeat the enemy quickly and efficiently are allowed in LOAC. The third principle, unnecessary suffering, directs that one may not employ weapons or projectiles that cause superfluous injuries or unnecessary suffering in enemy fighters. This principle is directed only to combatants, not civilians who should not be targeted at all. Finally, the principle of proportionality directs that civilian injury or loss of life, and damage or destruction of civilian objects, may not be excessive in relation to the direct and concrete military advantage to be gained. The problem with the four principles is definitional: what will “quickly” defeat the enemy? What injuries are “superfluous”? What incidental civilian death is “excessive” to a military advantage? Such answers as there are, are in this chapter.

Chapter 6 relates the individual status of the “players” on an armed conflict battlefield. It is the second question students should answer (after the conflict’s status) because the players’ status determines their rights and legal duties in the conflict. Civilians and combatants predominate, of course, but there are numerous subcategories for both: prisoners of war, retainees, militia, persons accompanying the armed forces, levée en masse fighters, spies, and mercenaries. Each category is explained and placed in relation to the other players. What if a civilian captured with weapons claims noncombatant status? LOAC provides for an informal tribunal. How is the familiar “farmer-by-day-fighter-by-night” dealt with? Who is an “unprivileged belligerent” and are they the same as an “unlawful combatant”? What status for a civilian who directly participates in hostilities and what are their battlefield rights, if any? Who is a “protected person” and what makes them such? These statuses and more are considered, along with their positions vis-à-vis the combatants who engage in combat with them.

Chapter 8 puts previous chapters to work by defining war crimes – their required precursors and circumstances – asking the reader whether real-life scenarios are, or are not, war crimes. The import of grave breaches is illustrated, including the factual World War II murder of fifty prisoners of war by Nazis, the subject of the motion picture, The Great Escape. When can a mosque be fired on, if ever? Are suicide attacks violations of LOAC? Is hostage-taking ever lawful? What is pillage? And “double-tapping”? On the battlefield, may one feign death? What if an individual volunteers to be a human shield? Are human shields ever lawful? Real-world war crime cases and their outcomes are related. “Disciplinary” war crimes, seldom noted, are, here, as well. Continuing, universal jurisdiction for war crimes turns out to be less than universal, and civilians can commit war crimes just as combatants can. Rape and other gender crimes are covered, here, as well. Four war crime trial records are included in the chapter’s Cases and Materials.

Chapter 1 relates a brief history of the law of war and the emergence of rules in conflicts. Those rules turned to royal mandates which, in turn, became laws that are today’s law of armed conflict, or LOAC. The chapter relates why modern states should obey the law of armed conflict – often referred to as “international humanitarian law.” The chapter details the five bases of LOAC: domestic laws, customary laws, treaties, judicial decisions, and publicists (i.e., academics). Common LOAC terms are explained to the student new to the subject. Finally, human rights, often seen as contrary or antagonistic to LOAC, particularly by the United States, is shown to now be complementary to LOAC, rather than contrary to it. This is essentially due to a still-evolving US position on the subject that is more willing to accept human rights objectives on the battlefield.

Chapter 11 is a brief chapter on seldom encountered legal issues: ruses and perfidy. Acts that invite an enemy’s confidence that he is entitled to protection under the rules of LOAC, with an intent to betray that confidence, is the crime of perfidy. It has been a codified war crime since 1907, though seldom prosecuted. False flags of truce, informing an opponent that the war is over so you can come on out, are perfidy, as is fighting in the enemy’s uniform. Feigning being wounded, however, is not perfidy, because it does not invite an enemy’s confidence. Examples in recent years are related: in Columbia against the FARC, in the Falklands against the British. Ruses, on the other hand, are lawful: deceit employed in the interest of military operations for the purpose of misleading the enemy. They do not invite the confidence of the enemy with respect to the protection of LOAC. Dummy artillery pieces, inflatable “tanks,” mock operations by nonexistent troops, all lawful.

Chapter 15 involves much of what has gone before; targeting both objects and human beings, core principles, individual status, and more. Artificial intelligence is described as applied to autonomous weapons, then as applied to LOAC’s core principles – difficult values for autonomous weapons to meet. To whom does criminal liability attach, should such weapons go awry? Designers? Builders? Users? These remain difficult LOAC issues that this chapter examines. Drones and their military use are discussed, including the American CIA’s use. Since CIA personnel are civilians, their involvement in targeting in armed conflict is unlawful, an issue discussed in this chapter. Targeted killing and its lawfulness are examined at length, as well as their relationship to assassination, an illegal act in US law. Targeted killing’s weak link, who decides which individuals should be killed, is also discussed. In the Cases and Materials section, the wrongful shooting down of an Iranian civilian airliner in 1988, that killed 290, is examined – a case study of autonomous weapons gone bad.

Chapter 12 explores rules of engagement. ROE are neither LOAC nor mentioned in the Geneva Conventions, but they are the important means by which commanders control use of deadly force by their subordinates. First appearing in the 1950’s US-North Korean conflict, they initially made little sense to warfighters. Their formulation is explained step-by-step in this chapter. ROE never limit the exercise of self-defense and they are not tactical in nature – never instructing combatants in how a mission should be executed. Instead, they restrict the use of force in certain circumstances, putting some targets off-limits, restricting the use of force in some locations. Junior officers seldom see the full ROE and troops never do; instead they are given greatly distilled versions, often on pocket-size cards. Before a US infantryman may fire in Afghanistan, for example, his ROE require that he observe “hostile intent,” or actually be the target of a “hostile act,” terms explained in this chapter. Other targets must be positively identified. It is understandable that infantrymen dislike ROE, but they are essential to the commander’s operational plans and helpful in the observance of LOAC.

Chapter 20 studies gas, biological, chemical, and nuclear weapons, looking at each of those prohibited weapons in turn. Poisonous gases were first banned in 1925 – but only their use, not their production or sale. There have been numerous uses of poisonous gases, including today in Syria. Biological and toxin weapons were banned in 1972, although their use is unmentioned in the 1972 Convention. A 1993 Chemical Weapons Convention, with a strict verification process, has been more effective. Russia’s continued poisoning of state critics is detailed as an example of state-avoidance of the 1993 Convention. CS (“tear gas”) use is limited by the 1993 convention but still employed as a riot control measure. There is no international law that makes nuclear weapons unlawful. Of the several multinational treaties that bear on nuclear weapons, the most significant is the 2017 Treaty on the Prohibition of Nuclear Weapons, which, so far, has but forty-four State Parties. None of the nine nuclear powers have joined, of course. In short, gas, biological, chemical, and nuclear weapons are abhorred and condemned until they are used; then the international community looks the other way.

Chapter 3 orients the student to the basics of LOAC as it exists on today’s battlefields. It moves from long-past history to modern, even contemporary, history by relating today’s LOAC, along with its more recent historical foundations and modern law of war incidents. For example, World War I and the ineffective trials of German war criminals by German courts – the Leipzig trials – are shown to be the impetus for World War II’s Nuremberg and Tokyo international military tribunals. The LOAC import of the League of Nations and the Spanish Civil War are detailed, along with the 1929 Geneva Conventions’ (two Conventions) contributions. The bulk of the chapter is an examination of today’s four 1949 Geneva Conventions, including their “common articles,” the varied routes to the charging of war crimes alleged against both combatants and civilians, along with the significance of “grave breach” war crimes. Indicators of war crimes is detailed, as well.

Chapter 17 attempts to pin down a moving target, cyber and its use and utility in armed conflict. The cyber targets chosen by China, Russia, Iran, and North Korea are detailed. The chapter defines cyber “attacks,” differentiating them from cyber “operations” – akin to a felony-misdemeanor distinction. Cyberattacks are found to be a use of armed force, in the sense of UN Charter Article 2(4), raising the right of victim states to respond with armed force in self-defense. Potential cyber conflicts are classified as international or non-international based upon their perpetrators. The difficulties of attribution of cyberattacks are detailed, including sovereignty and military necessity. A counter to cyberattack is belligerent reprisal, which is explored. Cyberattacks on critical national infrastructure (CNI) are a major problem. After defining CNI, the US position on responses is discussed. Recent changes in US cyber policy authorize far greater cyber retaliation and reprisal, as well as providing federal funding to carry them out. Finally, CNI’s weak link, the unwillingness of civilian corporations to fund their own cyber protection, is noted.