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To intervene or not to intervene? Military operations overseas

Throughout the Western world, and particularly in the UK, public and political opinion has become more sceptical over time about the practical value and moral legitimacy of military action overseas, whether on grounds of humanitarian protection or national interest. The sensitivity of public opinion to military casualties, together with constraints on public spending and the unconvincing outcomes of previous actions, means the threshold for future interventions may be high.


The rejection by the House of Commons of intervention in Syria in 2013 arguably strengthened its role in approving military action abroad. A rise in the frequency of jihadi violence, turmoil in the Middle East and revanchism in Russia all promise to raise questions and possible votes in the next Parliament about whether and how to intervene.

Humanitarian intervention

The Cold War had provided a rigid framework within which international conflict tended to take place. With the collapse of the Soviet Union, the US and the West in general felt more able to intervene directly in conflict situations. They were partly supported in doing so by the emergence of the 'Responsibility to Protect' doctrine, which gave grounds for humanitarian intervention in countries where the state was failing to prevent atrocities.

However, doctrines establishing grounds for humanitarian intervention have been difficult to put on a firm, objective footing.

  • Firstly, it has proved difficult to disentangle humanitarian objectives from national strategic interests.
  • Secondly, interventionist doctrines clash with a principle of the international system established at least since the 17th century: namely, that states are sovereign.

After the abuse of customary international law justifications of humanitarian intervention in the first half of the twentieth century, the UN Charter of 1949 makes no allowance for humanitarian military intervention that is not sanctioned by a suitable Security Council resolution.

But perhaps most importantly, doctrines have proved a poor guide to decision-making: while they may articulate noble intentions, they say nothing of the likely consequences of intervention, which have in practice depended on specific events and circumstances.

Interventions by the UK in Bosnia, Kosovo, Afghanistan, Sierra Leone, Iraq and Libya all took place under very different circumstances and had varying, and often unpredictable, outcomes. Success has depended not only on circumstance but also on subsequent commitment.

A particular lesson from Libya is that it may be unwise to bring down autocratic regimes without dedicating enough resources and persistence to the job of rebuilding. Dictators tend to rule using fear and division, and by hollowing out civic institutions; after they fall, the score-settling can be grisly.

Intervention in the next Parliament

The role of the House of Commons in approving overseas military operations is arguably stronger than ever.

The shadows of Iraq and Afghanistan mean that support for military intervention in the new Parliament is likely to be restrained, particularly when such action is not clearly backed by international law.

Some may consider that, in light of recent history, this cautious, case-by-case approach to intervention is a very good thing. However, in an international scene that looks increasingly disordered, others could be concerned that it leaves Britain hamstrung.

With a deadlocked UN Security Council, an overstretched military, and the absence of Parliamentary support for action in support of anything other than the most limited aims, the UK may be condemned to military intervention that does just enough to provoke a hostile reaction, but not enough to achieve any solid objectives.


How to win a Commons vote on military intervention

The conflict in Syria and Iraq embodies many of the usual features of the debate over intervention: weapons of mass destruction, gross human rights violations, Security Council deadlock, and the competing strategic interests of blocs and nations.

Having lost a vote on taking military action in Syria in 2013, the Government recalled Parliament for an emergency session in September 2014, and this time the Commons voted strongly in favour of participating in military action against ISIS in Iraq.

Three factors are likely to have played a role in the outcome of the ISIS vote:

  • The legality of action was broadly accepted. The Iraqi government had requested it, and the scope of the action was clearly defined in a long Government motion as being limited to Iraq.
  • The motion specified that no UK ground troops would be used, assuaging concerns about mission creep.
  • Following the emergence of videos depicting the beheadings of Western captives, public opinion swung substantially in favour of the airstrikes against ISIS during September 2014 (see Chart 1).
  • This suggests that ingredients of success in a vote on military intervention are, perhaps unsurprisingly, public consent, undisputed legality and clear limits on the scope of operations.


Chart 1: Public approving/disapproving of RAF air strike operations

Following the emergence of videos depicting the beheadings of Western captives, UK public opinion swung substantially in favour of airstrikes against ISIS.

Percentage of public approving/disapproving of RAF air strike operations against ISIS, YouGov surveys, 10-Aug to 26-Sep 2013

percentage of public approving/disapproving of RAF air strike operations against ISIS, YouGov surveys, 10-Aug to 26-Sep 2013


House of Commons votes on military action in the 2010 Parliament

  • 9 September 2010: Continued deployment of UK Armed Forces in Afghanistan. (Agreed 310 to 14)
  • 21 March 2011: (Retrospective) Approval for enforcement of no-fly-zone in Libya. (Agreed 557 to 13)
  • 29 August 2013: Military action to alleviate humanitarian suffering in Syria. (Defeated 272 to 285)
  • 26 September 2014: Use of UK air strikes to support Iraqi security forces' efforts against ISIL in Iraq. (Agreed 524 to 43)

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