When should countries intervene in others’ affairs?

The counterargument is that regime change can be a strategic or moral necessity, as was the case with the Second World War, and the Allied powers’ insistence on the unconditional surrender of Nazi Germany. Widespread revulsion at Nazi atrocities – most notably the Holocaust – inspired the 1948 Convention on Genocide, which established a moral imperative for the international community to intervene to prevent future crimes against humanity. More recently, the UN World Summit on 14–16 September 2005 affirmed that member states had the ‘Responsibility to Protect’ (RtoP) – invoked by Nato powers in 2011 to justify an intervention in Libya that led to the overthrow of Muammar Gaddafi.

With regards to the ongoing civil war in Syria, Bashar al-Assad’s backers (notably Russia and Iran) argue that any external intervention against his regime is inherently illegitimate and would destabilise the wider Middle East. However, Assad’s crimes against humanity – such as his use of chemical weapons against civilians – arguably threaten international peace and security, because of the chaos caused by the Syrian refugee crisis and the emergence of the so-called Islamic State.

In any such situation, both sides can point to internationally agreed principles approved by UN member states, and argue from irrevocably opposed concepts of sovereignty: does it convey complete protection for any regime, or can it be challenged by the international community in the name of RtoP?

"American foreign policy leaders argued that the US had a legal right to spread democratic government"

Katharina Rietzler, lecturer in American history at the University of Sussex

There is a tradition of American non-interventionism that goes all the way back to the early days of the republic. In 1821, US secretary of state John Quincy Adams put it most poetically when he declared that America “goes not abroad in search of monsters to destroy”, and should decline to become the “dictatress of the world”. But as the United States expanded, spurred on by a perceived moral duty to populate the continent, it forcefully intervened in the affairs of Native Americans and neighbouring Mexico as well as European imperial powers with interests in North America.

At the end of the 19th century, US statesmen began to experiment with the new language of humanitarian intervention. President William McKinley cited “the cause of humanity” when he decided to intervene in Cuba in 1898. American victory over Cuba’s colonial overlord Spain turned the United States into a world power, Cuba into an American protectorate and Guantánamo Bay into a naval base that remains part of a network of more than 600 US military bases on foreign soil today.

The Spanish-American War marked the beginning of a series of US military interventions in Latin American and Caribbean states, justified by US economic and strategic interests and the desire to keep European powers out of the western hemisphere. But American foreign policy leaders also argued that the United States had a legal right to intervene and to spread democratic government. After the many interventions during the Cold War confrontation with the Soviet Union, democracy promotion and humanitarianism ranked high as justifications for US engagement.

Today, non-interventionism and John Quincy Adams are enjoying new-found popularity in the United States. This is partly because of the costly, lengthy and unsuccessful wars in Afghanistan and Iraq after 9/11, and more recent American support for the war in Yemen, a humanitarian tragedy. But more fundamentally, and across the political spectrum, the idea that the United States should intervene even when American security is not directly threatened seems increasingly suspect.

"The ‘Responsibility to Protect’ mandate has raised ethical dilemmas that remain unresolved"

Rosemary Foot, professor and senior research fellow in politics and international relations at the University of Oxford

The UN Charter contained an understanding of state sovereignty that underlined the principle of non-interference in matters within the domestic jurisdiction of states. But in 1999, UN secretary-general Kofi Annan famously declared that the global community could not stand idly by watching gross and systematic violations of human rights, and that state sovereignty was being redefined to encompass the idea of individual sovereignty. Our contemporary reading of the UN Charter meant, he stated, that we were “more than ever conscious that its aim is to protect individual human beings, not to protect those who abuse them”.

Despite states’ overwhelming reluctance to support this stance, at the largest ever gathering of heads of state and government in New York in September 2005, UN members agreed a ‘Responsibility to Protect’ (RtoP) populations from mass atrocity crimes – that is, genocide, war crimes, ethnic cleansing and crimes against humanity. They also endorsed the idea that the international community should help states build a capacity to prevent abuse, using diplomatic, humanitarian and other peaceful means. If states were seen to “manifestly fail” in their duty of protection, external actors had a duty to provide a “timely and decisive response,” if mandated by the UN Security Council. Thus, RtoP’s significance relates to an apparent acceptance of international intervention, potentially to include the use of force, in the event of a ‘manifest failure’ to protect populations, and on the assumption that a government’s formal consent can be overridden.

Undoubtedly, it has proven difficult to implement RtoP in cases of need. States remain wary of the doctrine, especially weaker or ex-colonial states. Many believe that RtoP will be applied only selectively and when the interests of the powerful in world politics are engaged, and that if military force is used for humanitarian purposes, it might actually make matters worse for populations in peril.

When the UN Security Council applied RtoP in Libya in March 2011, it resulted in the overthrow and eventual murder of Colonel Gaddafi. While few lamented the demise of his murderous rule, the outcome for the Libyan population has been profoundly disturbing. RtoP has raised ethical dilemmas that remain unresolved.

"The consequences of so-called humanitarian interventions are invariably disastrous"

Geoffrey Roberts, emeritus professor of history at University College Cork, Ireland

Some argue that states violating human rights forfeit the right to non-interference in their internal affairs. Even more radical is the view that only states deemed ‘good’, according to the norms of western liberal democracy, deserve sovereign rights. This logic underpins liberal interventionism – the projection of western values into other states by military means. The unintended consequences of those so-called humanitarian interventions are invariably disastrous.

Can we stand idly by while governments commit genocide and monstrous dictators repress their own citizens? Yes, we can. And we should, if we want to avoid the mistrust, meddling and mayhem of a system without sovereignty.

Such a stance does not preclude states or the international community protesting against human rights violations. Nor does it preclude citizen action across national borders to support oppressed individuals and groups. There is no rule that governments have to maintain relations with states whose values they detest, though disengagement rarely inspires reform.

US secretary of state John Quincy Adams noted 200 years ago that, while America wished freedom and independence for all states, it was the power of its voice and its example that contributed to the cause, not the use of military force. Proponents of liberal interventionism often dub such sentiments isolationist. But sovereignty is not a constructed schema. Rather, it is an organic development arising from inter-state relations to help establish an international society of states with common practices, institutions and modes of behaviour.

Even a supposedly successful humanitarian intervention, by Nato in Yugoslavia in 1999, had its dark side. Though the intervention was motivated by attacks on the Albanian population in the Serbian province of Kosovo, both Serbs and Albanians were guilty of committing atrocities. The Nato bombing campaign forced Serbia out of Kosovo, along with 200,000 Serbian refugees.

Nato’s action was not authorised by the UN, and it soured western relations with Serbia’s ally, Russia. Kosovo remains somewhat isolated internationally, and its secession established a precedent that Russia invoked when Crimea seceded from Ukraine in 2014.

"Today, there are various facets of 21st-century life in which border lines don’t make sense: online or in space, for example"

J Simon Rofe, reader in diplomatic and international studies at SOAS University of London

According to the United Nations Charter, “nothing contained in the present Charter shall authorise the United Nations to intervene in matters which are essentially within the domestic jurisdiction of any state.” So even when crises happen, or when the apparatus of the state is persecuting its own people – as in Cambodia between 1975 and 1979, when more than 1.5 million people died – other states cannot simply walk in to ‘help’.

This approach centres on the concept of sovereignty, which to most people means control over a territory. We often think of those territories as having borders drawn on a map, but that has not always been the case. There was a time when humanity considered borders between polities – what we think of now as countries or nation states – as simply unnecessary. Today, too, there are various facets of 21st-century life in which border lines don’t make much sense: online or in space, for example.

Nonetheless, states guard their ‘sovereignty’ jealously. Again referring to the UN Charter, Article 51 states that “nothing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations.” It is perhaps no surprise, then, that this is one of the most referenced articles in the Charter: it allows countries to respond to attack. Yet the two most cited examples of UN military interventions – the operation in Korea 1950–53, and the expulsion of Iraq from Kuwait in 1990–91, were conducted under the aegis of UN Security Council resolutions (allowed for by Article 42).

Intervention is often thought of in military terms: tanks rolling past a border checkpoint, such as the Soviet interventions in Hungary in 1956 and Czechoslovakia in 1968, or intervening in failed states to assist in humanitarian crises, such as Operation Restore Hope UNITAF in Somalia (1992–93). However, the reality today is that intervention may mean intervening in international money markets or in online governance.

Complicating the picture still further, the intervening and the responses will be done less and less by other countries, and more and more by actors with only limited association with those countries within whose borders they reside at that point.

This content first appeared in issue 19 of BBC World Histories magazine