The principle of national sovereignty has been at the heart of international relations since the Peace of Westphalia was signed in 1648. The concept is based on two clear assumptions. First, that a state has territorial integrity and that only the people of that territory have the right to determine their political, economic and social development. Second, ‘external agents’ – including other states – do not have the right to intervene in another state’s affairs. The theory is that through this accord there can be peaceful coexistence in a world made up of states with differing political systems, religions and cultures.

However, state sovereignty implies that the prime responsibility for the protection of its people lies with the state itself. But as the International Commission on Intervention and State Sovereignty (chaired by the former Canadian Foreign Minister Lloyd Axworthy) declared in 2001: ‘Where a population is suffering serious harm, as a result of internal war, insurgency, repression or state failure, and the state in question is unwilling or unable to halt or avert it, the principle of non-intervention yields to the international responsibility to protect.’

Ten years later, the argument is still raging about whether this Responsibility to Protect (RtoP) has now evolved from being a widely accepted ‘norm’ to become an integral part of international law. And if the latter is the case, RtoP should oblige the international community to intervene in internal conflicts or humanitarian disasters, especially if that intervention involves military force, as is currently the case in Libya.

There is still a broad coalition of support for the NATO-led operation in Libya, which imposed a no-fly zone over the country as well as targeting the Gaddafi regime’s military assets, though significantly Germany has remained aloof. As Khaled Al-Duwaisan, Ambassador of Kuwait and Dean of the Diplomatic Corps in London, puts it: ‘Gaddafi made it clear to everyone when he said to the Libyan people: “Either I rule you, or I kill you!”’ The world simply could not sit by and watch the Libyan leader’s army march on the rebels’ stronghold of Benghazi and massacre the people there.

But if intervening militarily in Libya was the right course of action, why did this not happen in Yemen, where Ali Abdullah Saleh has clung onto power like a limpet, despite efforts by the Gulf Cooperation Council to arrange an exit strategy for him? Or in Bahrain, where security forces have killed unarmed pro-democracy protestors and the king called on Saudi troops to help quell unrest among the island’s Shia majority? Or indeed in Sri Lanka in 2009, when Tamil civilians were caught in the middle between advancing government forces and the separatist Tamil Tiger fighters, neither of whom seemed to display much concern for these people’s safety? The list goes on.

It is true that there has been a great reluctance on the part of the international community to take strong action against unpleasant regimes or governments that stand accused of human rights abuses, ever since the US-led invasion of Iraq in 2003. Even at the time, many countries – including UN Security Council member France – were against military action in Iraq, but retrospectively many others have considered the war to be a mistake. It has led to more deaths and suffering for the Iraqi people than under Saddam Hussein’s brutal dictatorship.

There was nonetheless widespread disquiet when the international community failed to intervene to stop the genocide in Rwanda in 1994. At least 800,000 people are believed to have been killed in that atrocity, according to the UN and countless more have lost their lives in the Democratic Republic of Congo subsequently, many of them refugees from Rwanda. In both cases, there were concerns in Europe and in Washington that the countries concerned were too far away, the logistics too difficult and that intervention in Africa could be seen as neo-colonialism. France was the ‘external agent’ that eventually took some action in Rwanda, just as it took the lead in helping oust President Laurent Gbagbo of Côte d’Ivoire earlier this year. President Nicolas Sarkozy was also one of the first to step up to the plate regarding Libya.

The role of the UN Security Council is critical, as it is seen as the body that can give legitimacy to any international action on the grounds of Responsibility to Protect. Security Council endorsement for such action often proved difficult in the past, however, not least because China has long refused to accept any watering down of a government’s sovereign rights over the country it rules. Russia, too, has sometimes proved averse to military action. But as the international lawyer and academic Philippe Sands has demonstrated in his writing, the global community is coming round to the idea that it cannot shirk its responsibilities when terrible things are going on somewhere around the globe.

The questions still remain to be answered definitively: when and how should action take place, and if no action, why not? After NATO decided to bomb Belgrade in 1999 – in the hope of protecting civilians in the largely ethnic Albanian Serbian province of Kosovo – there was a lot of international soul-searching. The then UN Secretary General, Kofi Annan, appealed to the organisation’s General Assembly for an answer to the question: ‘If humanitarian intervention is, indeed, an unacceptable assault on sovereignty, how should we respond to a Rwanda, to a Srebrenica [site of the infamous 1995 massacre of Bosnian Muslims], to gross and systematic violations of human rights that offend every precept of our common humanity?’

At the 2005 World Summit in New York, the issue of RtoP was discussed and the clearest guidelines so far were provided. In the summit’s ‘outcome document’ it was stated that each individual state is responsible to protect its population from genocide, war crimes, ethnic cleansing and crimes against humanity and that prevention should play an important part in that protective role. But equally it was accepted that the international community, through the UN, has the responsibility to use appropriate diplomatic, humanitarian and other peaceful means to help protect populations from genocide, war crimes, ethnic cleansing and crimes against humanity. And should such peaceful means be inadequate then the international community should be prepared to take collective forceful action, preferably in cooperation with relevant regional organisations.

But it was not until the International Commission on Intervention and State Sovereignty in 2001, mentioned earlier, that potential ground rules were set out. These included the need for a just cause, such as large-scale loss of life or ethnic cleansing. Any military action should only take place when other peaceful methods had failed. The force used should also be proportional and there should be a reasonable chance of success. The UN Security Council was deemed to be the most appropriate authority that could give the green light to such operations. And there should be clear objectives to any operation, as well as cooperation with humanitarian institutions.

Many would argue that is precisely the formula that has been pursued in Libya, though not everyone would agree. What is certain though is that there is no great appetite at the moment to try it anywhere else soon. Because no matter how clear the guidelines for intervention, the outcome remains an unknown entity.