After 9/11, military expenditure swelled around the world. Yet in light of the persistence of a range of different security threats, the results of this boost bear closer inspection, in order to determine whether increased spending in the defence sector has reinforced international security or jeopardised it. 

The recent dataset on military expenditures released by the Stockholm International Peace Research Institute (SIPRI) shows that spending on military infrastructure and technology has steadily increased on all five continents since the end of the Cold War, and particularly after 9/11. In a contrasting trend, the global number of terrorism-related fatalities in Organisation for Economic Cooperation and Development (OECD) countries increased by 650% in 2015. Spending in the security sector is aimed at ensuring security, but recent attacks in Manchester, Brussels and Paris suggest that resources to achieve this goal are not efficient enough in eliminating security threats, suggesting that there might be overspending in the defence sector. Recent defence empirics show that military spending is inversely correlated with economic growth, in the sense that military expenditures tend to have a robust negative long-term effect on gross-domestic product (GDP), with the strongest impact in OECD countries [1]. If more weaponry has failed to ensure international security and resilience, what is the rationale behind incremental budgetary allocations for military arsenals and tactical equipment? In real terms, is the possession of armament by countries across the world improving international security by minimising security threats or generating insurmountable security dilemmas? I argue that an efficient institutional response to threats to stability and security requires a systematic and consistent analysis of (i) the long-term implications of increasing military expenditures and (ii) of the prospects of a more integrated approach to eliminate security risks.

The major justification to legitimise investments in military technology has been the need for a new policy response model to the internationalisation of security risks and regional crises, such as that in Ukraine. Political leaders reiterated the need to increase defence and security budgets in order to be able to respond to threats to national security. Recruiting new military personnel and developing military technology has become a top-priority on policy agendas. For example, US President Donald Trump proposed a boost in the military expenditures for 2018 by 10%. The German Bundeswehr has expanded significantly in both number of troops and military technology under Defence Minister Ursula von der Leyen. The recent increase in the military spending is also linked to North-Atlantic Treaty Organisation (NATO) member states’ collective (non-binding) agreement to allocate at least 2% of the GDP to the defence sector by 2024. This defence spending requirement is based on the logic of deterrence and has as objective to counterbalance defence capacities of other major powers, such as Russia. While defence alliances ostensibly enhance collective security, there might be a false promise contained within the 2% NATO spending requirement.

Can the logic of deterrence ensure a stable international security order?

Increased military spending and arms race policies rest on the logic that the level of mutual destruction caused by the hypothetical use of the military capacity deters nation states from actually going to war against each other. Empirically, the nuclear deterrence theory was discredited by the Kargil War 1999 when India and Pakistan, both in the possession of nuclear technology, went to war.

Superior military arsenals and weaponry, understood as ‘survival mechanisms’ in the international system [2] bring net security assets, but might miss the point in eliminating salient security threats, such as (transnational) terrorism and armed conflicts, which result in thousands of fatalities every year. Additionally, the continuous investment in the defence sector and military technology might turn into security dilemmas [3, 4, 5], i.e. situations in which the acquisition of military capacities generates similar responses from regional neighbours, thus creating tensions which can escalate into security crises and inter-state conflicts. One state’s security is another state’s insecurity and the question of “How much military capability is enough to ensure stability and security?” becomes increasingly prominent.

Defence alliances can maximise the relative power of individual (state) actors on one side and generate a multipolar system with many sites of authority on the other side, which, from a realist perspective is more stable than bipolar international systems [6]. Nonetheless, alliances seem to become increasingly unstable in the contemporary world order. The failure to form a stable alliance which would end the conflict in Syria,  Brexit and the US blitz-withdrawal from the Trans-Pacific Partnership and Paris climate accord represent only some examples suggesting the relative instability of international agreements.

The deterioration of collective security might be attributed to the overall decline in popularity of international security organisations, which have emerged as a promoter of international cooperation and security after the Second World War. Mounting criticism, particularly related to the decision-making mechanism in the UN Security Council and NATO policy has destabilised their position in international politics after the end of the Cold War.

The challenges confronted by collective security seem to motivate states to rely on self-help principles and to incline more towards preserving their sovereignty. Is this suggesting a decline of the rules-based liberalist order and a return to an international system dominated by power politics?

Return to realism: The greatest challenge of the 21st century?

What is the reason for the decline in cooperation and tendency towards more national solutions to achieve political outcomes? There could be several empirical explanations for the decrease in the political momentum and élan of liberalism and diplomatic cooperation. Firstly, the failure of the liberalism promise [7], in particular economic liberalism, to provide a sustainable framework for social justice and equality. The exclusion of parts of the society from political participation has been the main root cause for armed conflicts and extremist violence in the new millennium. Secondly, multiple (partially) failed military interventions, e.g. in Iraq, Afghanistan, or Bosnia, as well as the inability of international organisations to provide sustainable mechanisms for ending conflicts in Syria, Libya or Ukraine have generated an insurmountable lack of confidence related to the ability of alliances to deliver efficient and sustainable results. This, along with demands for migration management, has determined a re-focus on more national solutions.

Rational choice theoretical approaches, such as Nash’s equilibrium and Adam Smith’s economic liberalism model, suggest that mutual cooperation between actors maximises their overall gains. If the expected utility from cooperation would make states better off, what prevents them from doing so? Presumably, it is the lack of trust and mutual suspicion of defection or non-compliance emerging from information asymmetry which generates reluctance towards engaging in alliances or ex-ante agreements. An unstable ground for cooperation weakens multilateralism and inter-gouvernmentalism, in other words, the role of international organisations in maintaining international security. While a perfect Nash equilibrium is assumed to be utopic, an approximation towards it through stabilising cooperative bodies and consolidating stability could be a tangible achievement.

With an increasing number of dilemmas related to political preferences, foreign policy choices and future security scenarios, the question: “Will the expansion of the defence sector trigger the wars of tomorrow?” seems legitimate.

Risks to international security

Despite an expansion of the defence and security sector, terrorism has continued to occur and even intensified dramatically in OECD countries. The increase in military expenditures has also generated a series of risks which might jeopardise the goal of international security and stability.

Firstly, the expansion of the defence sector could increase the risk of radicalisation of vulnerable individuals, because it can be inferred that expenditures in the defence sector occur at the expenses of spending in development, social and human security sector. As recent research using cross-sectional data suggests, military spending is negatively correlated with economic growth. This is likely to have an uneven social impact, with poor people and vulnerable groups being more affected, increasing thus their likelihood to be attracted by the extremism trap. This makes it easier for terrorist groups to recruit adherents and persuade them to perpetuate acts of terrorism. It is acknowledged that security technology and capability contributes to thwarting terrorist attacks and that perfect security is utopic. Nonetheless, the persistence of lone-wolf as well as coordinated attacks in Europe despite the boost of security and defence systems highlights the possible inadequacies of military approaches and the need for more efficient models of security governance addressing the new security threats.

Secondly, an increase of the defence and military sector empowers the military and enhances its influence in decision-making. The militarisation of security and defence policies might generate a dilemma of democratic rights vs military effectiveness, as was highlighted during the extended state of emergency in France after the series of coordinated terrorist attacks in 2016. A further potential security risk posed by a continuously incremental defence sector is the tendency towards ‘hawkish’ politics, as outlined by the US decision to intervene in Iraq. Increased availability of military technology might be associated with higher probability of (non-essential) interventionism, which generates new spill overs of violence and terrorism.

The emergence of counter-narratives such as Disarmament, Demobilisation and Reintegration (DDR) under the UN Disarmament and International Security Committee (DISEC) emphasises the need to raise awareness about the risks which an inflationary arms availability can pose to international security. As a deterrence mechanism, military capacity is aimed at inhibiting the states’ preferences for initiating war. Nonetheless, the substantive implications of a (steadily) increasing defence sector for security and stability middle- and long-term need to be closer assessed. Under the sustainable imperative imposed by the logic of ‘survival’ (Waltz 2010), security approaches need to be streamlined towards more viable and non-destructive models.

Could less be more? Implications for EU security and defence policy

The recent changes in the international security order yield reforms to accommodate the new security challenges and discontinuities. While the possession of military arsenals serves as a genuine self-defence strategy, it also unleashes tensions which might pose greater security risks than those which it is aiming  to prevent. There is potential to minimise the gaps associated with the risks posed by the current military policy to international security and to streamline security approaches, at three levels.

Firstly, a more consistent analysis in terms of cause and effect of domestic and international security responses needs to be undertaken. Constantly expanding military technology is creating a spiralling security dilemma and raises the question: how much military is enough? A re-distribution of defence spending towards social policy sector might decrease the risk of radicalisation, which has been the major cause of terrorist attacks in Europe so far. Policy responses to provide security could be designed towards demilitarisation and prevention. While encouraging stronger collective security and cooperation, the EU should avoid falling in the pitfall of becoming a proxy in the continuation of Cold War politics. Good and symmetric relations with both Eastern and Western partners are of substantive importance, given the nature of risks posing the most substantial threats to European security at the moment.

Secondly, while strengthening the alliance with NATO, the EU could consider re-focusing on defence options ‘from its own garden’, with the possibility of integrating them into the NATO policy. The advancement of EU battlegroups under the Common European Defence and Security Policy, as well as the joint plan between France and Germany to develop a fighter jet ‘made in EU’ represent tangible steps in this regard. The EU battlegroups represent “military instrument[s] for early and rapid responses” under the control of the Council of the European Union, consisting of (currently) 18 battalions with soldiers stemming from EU member states. This represents an example of investment into a common quasi-army and military strength which is not under the lead of any particular nation, and can benefit all EU Member States simultaneously. This model of security might eliminate some of the regional security and social dilemmas associated with a continuous arms race policy between individual states and could be considered by other regional organisations such as ASEAN and Mercosur. Given the non-binding character, a reversal from the NATO spending requirements is a scenario which might be worthy of closer consideration. However, the support of political parties in EU NATO members states for this policy option is currently low. In Germany, an important member state for the future of EU defence and security policy, two major parties, Social Democratic Party (SPD) and the Green Party (Bündnis 90/Die Grünen), reject the NATO two per cent military spending requirement.

Thirdly, increased awareness about the implications of arms trade and military technology on security and stability as well as more efficient arms control and arms export is necessary. While manufactured to ensure security, weapons can themselves become instruments of insecurity. Reform of arms trade agreements and regulation of weaponry possession and arms exports at intergovernmental levels of governance must aim at having greater binding potential. Historically, very little has been done in this respect because of an increasing interest of arms manufacturers to maximise their profit.


[1] d’Agostino, Giorgio; Dunne, Paul J.; Pieroni, Lucia (2017): Does Military Spending Matter for Long-run

Growth?. In Defence and Peace Economics. 28 (4), pp. 429-436.

[2] Waltz, Kenneth Neal (2010): Theory of international politics. Reissued. Long Grove, Ill: Waveland Press, Chapter 6.

[3] Herz, John H. (1950): Idealist Internationalism and the Security Dilemma. In World Pol. 2 (02), pp. 157–180. DOI: 10.2307/2009187.

[4] Glaser, Charles L. (1997): The Security Dilemma Revisited. In World Politics 50 (1), pp. 171–201.

[5] Tang, Shiping (2009): The Security Dilemma. A Conceptual Analysis. In Security Studies 18 (3), pp. 587–623. DOI: 10.1080/09636410903133050.

[6] Morgenthau, Hans J.; Thompson, Kenneth W. (1985): Politics among nations. The struggle for power and peace /  Hans J. Morgenthau, Kenneth W. Thompson. 6th ed. New York: Knopf.

[7] Mearsheimer, John J. (1994/95): The False Promise of International Institutions. In International Security 19 (3), pp. 5-49.

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