The conclusion revisits the complementarities between CHA and other methodologies. It emphasizes that exploration and testing are equally important for translating results into answers. It discusses the historical origins of the logical positivists’ distinction between domains of discovery and confirmation, in order to underscore its artificiality and misrepresentation of the actual scientific process. It highlights four contributions that CHA makes to social inquiry more broadly: the centrality of historical thinking across all methods, the beneifts of greater ontological transparency, the importance of paying attention to testworthiness of hypotheses, and the inescapability of methodological heterodoxy.

This chapter covers three areas of international law that, though distinct, are interconnected. The law of statehood defines which entities qualify as states, the most important actors on the world stage and the international legal persons with the most rights, duties and functions. The law of self-determination accords rights to ‘peoples’ rather than to states, but in limited circumstances it enables peoples to create new states for themselves. That can be a way for a people to seize control of its own destiny, especially if it has been subject to colonialism or oppression. Finally, the law of territory determines the geographical borders within which many of the rights, duties and functions of states are applicable, including how those borders can change.

Under international criminal law (‘ICL’), individuals can be prosecuted and punished for conduct that is criminalised under customary international law and/or treaty. This differs from most branches of international law, which concern the rights and obligations of states. The rationale for holding individuals to account for such crimes was articulated in 1946 by the International Military Tribunal at Nuremberg, which stated: ‘Crimes against international law are committed by [people], not by abstract entities, and only by punishing individuals who commit such crimes can the provisions of international law be enforced.’ This chapter introduces this branch of international law, citing examples involving Australia as well as many other states. The chapter gives an overview of some of ILC’s key principles and aims, andoutlines the historical development of ICL. It explains how ICL is currently being enforced, considers the core crimes in ICL and discusses individual criminal responsibility and defences.

The previous chapter described the extent of a state’s physical territory; this chapter looks at how far a state’s legal power extends. As will be seen, international law places certain limits on the right of a state to make, apply and enforce its laws – its jurisdiction – and these limits are considered in Section 6.2. International law also recognises two principal bars to the exercise of that jurisdiction: diplomatic immunity and state immunity; these are covered in Sections 6.3 and 6.4. Two other bars to jurisdiction, namely special mission immunity and the foreign act of state doctrine, are also briefly covered in Sections 6.6 and 6.7.

International humanitarian law (‘IHL’), also known as the law of armed conflict (‘LOAC’), is a branch of international law that regulates the behaviour of participants in armed conflicts and encompasses rules on the military targeting of persons and objects, the means and methods of warfare, the protection of persons and objects, and the implementation and enforcement of the law. International humanitarian law is also one of the most highly codified fields of international law, with numerous treaties adopted over the last 150 years; many of these have also attained customary status. In developing IHL, states have recognised that, while the ultimate aim of society should be to strive to prevent war, wars will nonetheless occur, and that while ‘war will always constitute suffering and personal tragedy … rules of warfare are intended to prevent unnecessary suffering that yields little or no military advantage’. This balance between humanitarian aims and military objectives serves as the basic underpinning of all the modern laws of armed conflict.

The Australian legal system is not an island, and Australian law has felt the influence of law and legal ideas from other jurisdictions, particularly other common law countries. Australian law has also been shaped by public international law both directly and indirectly and this interaction has become increasingly important as the scope and content of international law have grown. The relationship between Australian law and international law is mediated by Australia’s constitutional framework in which the separation of powers between the executive, legislature and the courts holds central place. Unlike the constitutions in many other legal systems, the Australian Constitution does not address the relationship between international and domestic law, and most of the relevant legal principles are to be found in the common law. This chapter examines how each arm of government in Australia has engaged with international law, identifying areas where the relationship is well settled (as it is in relation to treaties) and areas where there remains some uncertainty (as in relation to customary international law).

States often need to cooperate with each another to address legal and other issues of common concern across many fields in an interdependent world. International organisations (‘IOs’) emerged in the 19th century as a means of intensifying and permanently institutionalising international cooperation, through bodies with an international legal personality, and functions and powers, separate from their member states. While the earliest IOs had a narrow technical focus, the League of Nations (1919–46) and United Nations (since 1945) reflect a more ambitious global agenda of broad-spectrum cooperation. The proliferation of IOs has generated some key legal issues which this chapter explores: how to define IOs; the nature, extent and consequences of their international legal personality; their powers, immunities and privileges; and the scope of their legal responsibility for their conduct. There is a special focus on the United Nations, as a universal IO with competence in many areas of international life and human activity, and from whose establishment and practice much of the international law of IOs has emerged.

This chapter covers the international law governing the use of force between states – the jus ad bellum. This is in contrast to the jus in bello – the law of armed conflict, or international humanitarian law – which regulates the conduct of hostilities once under way (see Chapter 11). Since at least 1945 the use of force by states has been prohibited, except in self-defence or when authorised by the United Nations Security Council. This chapter analyses the prohibition, the two exceptions, and the controversial issue of humanitarian intervention and its close relative, the ‘responsibility to protect’.