Chapter 5 examines functional magnetic resonance imaging (fMRI) as a transformative neuroimaging technique that maps brain activity by detecting changes in blood oxygenation. The chapter traces fMRI’s development from Angelo Mosso’s 19th-century observations of blood-flow changes during neural activity to Seiji Ogawa’s pioneering work with blood oxygenation level-dependent (BOLD) contrast in the 1990s. It discusses the neurophysiological basis of the BOLD signal and how increased neural activity triggers disproportionate increases in cerebral blood flow relative to oxygen metabolism, creating measurable magnetic susceptibility differences. The text analyzes the temporal profile of the hemodynamic response, with its characteristic delay, peak, and undershoot, emphasizing its implications for experimental design. Considerable attention is given to the methodological complexities of fMRI research: preprocessing steps (slice-timing correction, motion correction, coregistration), statistical analysis approaches (including voxel-wise comparisons and region-of-interest analyses), and techniques for examining functional connectivity between brain regions. By evaluating fMRI’s comparative advantages, which is exceptional spatial precision and its noninvasive nature, alongside its limitations in temporal resolution and indirect measurement of neural activity, the chapter discusses fMRI as a powerful, albeit technically demanding, tool that provides unique insights into functional brain organization while requiring rigorous experimental design and statistical analysis.

Chapter 4 examines magnetic resonance imaging (MRI) as a cornerstone technology for visualizing brain structure with remarkable precision. The chapter traces MRI’s development from Wolfgang Pauli’s discovery of nuclear spin properties through Nobel Prize-winning innovations by Bloch, Purcell, Lauterbur, and Mansfield that enabled spatial encoding of magnetic resonance signals. It explains the physical principles underlying MRI and how powerful magnetic fields align hydrogen atoms in tissue, followed by precisely tuned radiofrequency pulses that excite these atoms, resulting in detectable signals that vary by tissue composition. The text explores technical considerations essential for high-quality image acquisition, including magnetic field strength, head coil design, and pulse sequence parameters that determine tissue contrast in T1, T2, and FLAIR imaging. Considerable attention is given to image processing methods, distortion correction, registration, normalization, segmentation, and smoothing that prepare brain images for meaningful analysis. By assessing MRI’s comparative advantages over other structural imaging modalities, including its non-ionizing radiation profile and superior tissue differentiation, alongside practical considerations of safety protocols and experimental design, the chapter discusses MRI’s foundational role in modern neuroimaging while acknowledging the tradeoffs between spatial resolution, acquisition time, and signal quality that researchers must navigate when designing studies.

Chapter 14 allows us a look at the trajectories in brain imaging technology and research while acknowledging the field’s unpredictable evolution. It examines how existing tools are being refined, with functional MRI achieving submillimeter resolution and EEG sampling rates reaching 100,000 Hz, while highlighting the growing influence of private industry through initiatives like Neuralink, Facebook’s Building 8, and Google Brain. The chapter analyzes the scientific value of multimodal imaging approaches that combine complementary techniques such as EEG-fMRI to leverage both high temporal and spatial resolution. It discusses how large-scale collaborative efforts including the Human Connectome Project and Brain Initiative are reshaping our understanding of neural connectivity despite the challenges of modeling the brain’s extraordinary complexity. The emergence of biomarkers receives particular attention, emphasizing how machine learning algorithms are enhancing our ability to detect neurological and psychiatric conditions through brain imaging data. Recent technological innovations are surveyed, including miniaturized MRI scanners, real-time imaging analysis, optically pumped magnetometry, and functional ultrasound imaging, all pointing toward more accessible and sophisticated brain measurement capabilities. The chapter concludes with practical guidance for newcomers to the field and consideration of ethical dimensions, emphasizing that brain imaging technologies should advance human wellbeing rather than enable control or manipulation. Throughout, the chapter maintains that while specific trajectories remain uncertain, the overall direction is toward increasingly precise, accessible, and clinically valuable brain imaging technologies.

This chapter explores the different forms strategy can take in practice. This involves, in the first instance, looking at offence, defence, deterrence, compellence, offence, and the miscellaneous uses of force. From this conceptual basis, the chapter ends with an examination of strategy in the contemporary setting. This includes a synopsis of the current state of the strategic landscape, identifying the most important trends and challenges extant in strategy. The four areas covered are the Ukraine War, technology (cyber power and unmanned systems/AI), nuclear weapons and strategic ethics.

Chapter 12 examines the methodological foundations for conducting effective brain imaging research, positioning experimental design as the cornerstone of meaningful neuroscientific inquiry. It outlines a systematic approach to developing experiments, beginning with the essential groundwork of literature review and theoretical development before proceeding to stimulus creation and experimental implementation. The chapter emphasizes the critical balance between simplicity and complexity in design, advocating for well-controlled paradigms that isolate specific cognitive processes while acknowledging the brain’s inherent complexity. Particular attention is given to the technical considerations unique to different imaging modalities, addressing how fMRI’s hemodynamic response requires different design considerations than EEG’s direct measurement of neural activity. The chapter explores the philosophical challenges of constructing appropriate control conditions that effectively isolate the cognitive processes of interest, comparing cognitive subtraction approaches with factorial designs that reveal interaction effects. It emphasizes the importance of piloting experiments to identify potential confounds like expectancy bias and the role of jittered intertrial intervals in minimizing such effects. Throughout, the chapter underscores that experimental design in neuroimaging requires interdisciplinary expertise: understanding of brain anatomy and physiology, mastery of imaging technology, and sophisticated experimental psychology skills to translate abstract cognitive concepts into operationalizable experimental paradigms.

This chapter surveys modern experiences with irregular warfare from the Second World War until today. Specific attention is paid to the ‘golden age of counterinsurgency’ during the Cold War as well as its more recent ‘renaissance’ and expansion, to include counterterrorism, in Iraq, Afghanistan and globally. The themes here are continuity and change: the former in the shape of relatively unchanging principles based on best practices, and the latter in terms of organisational adaptation, most frequently in the form of specialised units. The chapter identifies and explores four pathologies related to irregular warfare that make countering or conducting it difficult, including mistaking ways for ends, politicisation, over-inflating or mirror-imaging an opponent and the agency of groups too often assumed to be under your control. It concludes by addressing myths associated with specialised forces and irregular warfare and suggests that success results from understanding this form of warfare’s highly political nature.

This concluding chapter notes how changes in the strategic and intellectual environments have been reflected in the three editions of Understanding Modern Warfare. At the same time, it is noted that certain themes and principles have remained constant through all editions. This reflects warfare itself, which is characterised by continuity and change. To illustrate, the chapter identifies eleven constants and five areas of change. It is concluded that the art of war is, at least in part, concerned with finding an equilibrium between these two positions. The practitioner must adapt to change, while still respecting the enduring nature of war.

This chapter outlines the environmental characteristics of air power, particularly the challenges of operating in the air environment. It introduces readers to the way in which modern air operations began during the First World War and the subsequent theorising by a number of key figures who focused upon the strategic aspects of air power and the belief that air power could bring about rapid and decisive victories. These theories are contrasted with the events of the Second World War, which led not to independent air power but the further illustration of the importance of air power as a whole, operating both independently of surface forces and alongside them as a precursor to discussion in Chapter 11.

This chapter argues that the future form of land warfare is far from certain. For some, the future is net-centric warfare, an information and technology-focused view on the changing character of warfare. To meet the demands posed by the changing character of conflict, armies must embrace the theme of multi-domain operations. However, history suggests that in the future multiple forms of land warfare are likely to coexist because the practice of land warfare is shaped by many different political, economic, social and cultural contexts.

This chapter helps readers make sense of the array of activities that can be considered as irregular warfare. As an umbrella term for a particular form of warfare, its methods consist of terrorism, insurgency, revolution, coup d’état and civil war. The chapter compares and contrasts these methods according to the level of resources they employ, their respective centres of gravity, strategic and tactical orientations, mechanism for success and duration. It provides a useful taxonomy for students seeking to better comprehend irregular warfare but narrows down subsequent study to its two most prevalent methods: terrorism and insurgency.