The 20th century was a bloody canvas of human history, etched with an estimated 187 million deaths directly or indirectly linked to its wars. This staggering toll represents over 10% of the global population as it stood in 1913, according to historian Eric Hobsbawm's assessments.
Hobsbawm divides this tumultuous century into three distinct phases. The first, from 1914 to 1945, was marked by an 'era of world war' largely centred on Germany. This period, often viewed as a single '30 years' war', saw massive conflicts between territorial states and their alliances. This was followed by the 'era of confrontation between the two superpowers' from 1945 to 1989 – the Cold War. While not always involving direct combat, this era was defined by a persistent 'will to contend by battle', aligning with Thomas Hobbes's definition of war.
The third phase, from the end of the Cold War onwards, has seen a continuation of military conflict, particularly in Europe, Africa, and Western and Central Asia. A notable shift highlighted by Hobsbawm is the changing nature of warfare itself. Armed operations are no longer exclusively the domain of governments or their authorised agents. Furthermore, the contending parties often lack common characteristics, status, or objectives, beyond their willingness to employ violence – a far cry from the inter-state wars that largely defined the earlier parts of the century.
Geographically, the impact of these conflicts has been uneven. While Europe, historically a primary theatre of war, has largely been free of inter-state conflicts since 1945 (with the notable exception of the south-east in the 1990s), other regions have seen escalating violence. The Middle East and South Asia experienced endemic inter-state wars during the Cold War era, often linked to global confrontations. Sub-Saharan Africa, comparatively less affected in the early 20th century, became a significant theatre of armed conflict in the latter half, enduring immense suffering.
For British policymakers, understanding these historical patterns is crucial for informing foreign policy and defence planning. The shift from large-scale state-on-state conflicts to more diffuse, non-state actor-driven violence presents new challenges for global security – necessitating adaptable strategies that take into account the UK's own interests and commitments abroad.