7.4 Global Security Challenges

What does it mean to be safe?

For much of the twentieth century, "security" in international relations meant one thing above all: military security, the protection of states from external armed attack. The Cold War, with its nuclear arms race and superpower rivalry, was the perfect expression of this traditional view. But that understanding has expanded dramatically in recent decades.

Scholars and policymakers increasingly recognise that threats to human well-being come from many sources beyond military attack. Terrorism, climate change, pandemics, cyber-attacks, organised crime and resource scarcity all pose serious security challenges -- and none of them respects national borders. This broader understanding is captured in the concept of human security, which shifts the focus from the security of states to the security of individuals. The United Nations Development Programme introduced the idea in 1994, identifying seven dimensions: economic, food, health, environmental, personal, community and political security. This chapter examines some of the most pressing global security challenges of our time, and how our very definition of safety has widened.

Terrorism, and the difficulty of even defining it

Terrorism is generally defined as the deliberate use of violence against civilians or non-combatants to create fear and achieve political, religious or ideological objectives. Its key characteristics include the targeting of civilians to maximise fear and media attention, a political rather than purely criminal motivation, an intent to communicate a message to a wider audience beyond the immediate victims, and the involvement of non-state actors, though states can also sponsor terrorism. It comes in several forms, and a balanced account names them across the spectrum: religiously motivated terrorism (such as al-Qaeda or ISIS), ethno-nationalist terrorism (such as historical Basque or Kurdish separatist groups), far-right extremism (including the 2011 attacks in Norway and white-supremacist violence), and far-left extremism (such as the historical Red Army Faction). It is important to note, neutrally, that "terrorism" is a contested term -- the saying that "one person's terrorist is another person's freedom fighter" reflects how the label is often applied selectively for political purposes, and international law still lacks a universally agreed definition.

The attacks of 11 September 2001, in which nearly 3,000 people were killed in the United States, fundamentally changed the global security landscape and triggered the "War on Terror." This response, examined here in a balanced way, included the invasion of Afghanistan in 2001 to overthrow the Taliban regime that harboured al-Qaeda, the invasion of Iraq in 2003 (justified partly by claims of weapons of mass destruction that were never found), expanded surveillance programmes, drone strikes in several countries, and the detention centre at Guantanamo Bay where suspects were held without trial. The War on Terror raised profound questions about the balance between security and civil liberties and the effectiveness of military responses. Critics argue the invasions created more instability and radicalisation than they prevented; supporters argue aggressive action was necessary to disrupt terrorist networks and prevent further attacks. Twenty years on, the US withdrawal from Afghanistan in 2021 and the Taliban's return to power reopened the question of whether two decades of intervention achieved lasting results -- a debate the chapter presents without taking sides.

The new frontiers of insecurity

Beyond terrorism, several other security challenges have risen to prominence, and they show just how far the concept of security has expanded. Nuclear proliferation -- the spread of nuclear weapons -- remains one of the gravest threats; nine states currently possess nuclear weapons, and while the Treaty on the Non-Proliferation of Nuclear Weapons aims to prevent further spread, challenges persist from states like North Korea and concerns about Iran's programme. Cyber warfare sees states and non-state actors using digital attacks to disrupt critical infrastructure, steal secrets and spread disinformation; attacks on power grids, financial systems and elections represent a new frontier, made especially difficult by the problem of attribution -- identifying who actually carried out an attack in cyberspace.

Climate change and environmental security is increasingly recognised as a "threat multiplier" that worsens existing risks: rising seas, extreme weather, water scarcity and competition for shrinking arable land can drive displacement, resource conflicts and state instability, as in the Sahel region of Africa. Pandemic threats moved to the centre of attention with COVID-19, which showed how quickly a health crisis can become a global security challenge, disrupting economies and deepening divisions. And disinformation and hybrid threats -- the deliberate spread of false information to undermine democratic institutions, elections and public trust -- represent a growing concern that blurs the line between war and peace. A crucial pattern unites all of these: most modern security threats are transnational, crossing borders and requiring international cooperation to address. The relationship between traditional military threats and these newer, non-traditional ones is itself an important question. The world has not left old dangers behind -- nuclear weapons and interstate rivalry remain -- but it now faces a wider and more interconnected web of threats, which is why the very meaning of security has had to grow.

In short

The concept of security has expanded far beyond its Cold War focus on military defence of states, toward the idea of human security centred on the well-being of individuals. Terrorism -- the deliberate use of violence against civilians for political ends -- remains a major threat, though defining it is politically contested, and the response to it, the War on Terror, raised debated questions about effectiveness and civil liberties that the chapter presents without taking sides. Newer challenges include nuclear proliferation, cyber warfare with its problem of attribution, climate change as a threat multiplier, pandemics and disinformation. What unites most of these is that they are transnational, requiring international cooperation -- which is precisely why our very understanding of what it means to be secure has had to grow.