The following is a guest post by Thomas Obel Hansen, who is is the Beatriz Galindo Distinguished Professor with the Department of International Law, Universidad Carlos III de Madrid; he has a research affiliation with the Transitional Justice Institute, Ulster University.

Why Spain is right to stand up for international law in the US/ Israel war on Iran

The Spanish government should be lauded for standing up for international law in the current war of aggression against Iran. Whereas many States in the West have stated broad support of the goals pursued by the US and Israel in Iran – and have been mainly muted about the fact that this military campaign is manifestly illegal – Pedro Sánchez’ government in Spain has taken a fundamentally different approach. Sánchez has said “no to war”, insisting – and rightly so – that US/ Israel military action in Iran is “unjustified, dangerous and illegal”. 

This position is coupled with real action not to be complicit in a war of aggression, including denying the US the right to use Spanish military bases to assist Operation Epic Fury. This has triggered anger in Washington, with President Donald Trump calling Spain “terrible” and threatening to “cut off all dealings with Spain”. President Trump also suggests the US could simply ignore Sánchez’ decision and continue to use the military bases in Spain: “if we wanted, we could just fly in and use it; nobody’s going to tell us not to use it”. If doing so, that would amount to yet another breach of UN Charter law.

Sánchez responded to these suggestions in a televised address on March 4, stating that Spain will “not be complicit in something that is bad for the world – and that is also contrary to our values ​​and interests – simply out of fear of reprisals from someone”. That response should be read in a context where Spain has been among the most vocal voices in the West condemning the genocide in Gaza and – unlike many others – taken meaningful measures to address it. This has caused friction with the US and Israel.

Sánchez was also among the few leaders in the West to explicitly condemn recent US military action in Venezuela, callingit “a terrible precedent” which “reminds us of past aggressions, and pushes the world toward a future of uncertainty and insecurity, similar to what we already experienced after other invasions driven by the thirst for oil”. The Spanish government has also clearly rejected US ambitions to take over Greenland, stating that “we cannot accept the explicit threat to the territorial integrity of a European state, as is the case with Denmark.” In that latter instance Spain has not been alone, as many European leaders pushed back against President Trump’s aspirations with reference to rules in international law prohibiting the use of force outside of situations of self-defence or UN Security Council authorization. 

Coming back to Iran, in contrast to Spain, several key countries in the West are downplaying – or simply ignoring – the relevance of international law to the military action initiated by the US and Israel. Suggestive of this trend, German Chancellor Friedrich Merz has stated his view that “classifications [of the Iran attack] under international law will have relatively little effect”, in that regard refusing to “lecture” Germany’s allies while stating support for “many of their objectives” in Iran.

These suggestions follow in the wake of a joint statement by Germany, France and the UK, condemning Iran’s retaliation in the form of “indiscriminate and disproportionate missile attacks” against countries in the region – a statement which did not touch on the legality and legitimacy of US/ Israeli strikes that preceded Iran’s action.

Britain has in recent days announced an approach that even if it will not “join offensive action” against Iran, it will permit the US to use its military bases for what it calls “specific and limited defensive purpose” (understood to involve destroying Iranian missiles “at source – in their storage depots or the launchers which [are] used to fire the missiles”). Permitting this, Britain refers to “collective self-defence of regional allies”. British officials have later clarified that they would not rule out the possibility that its own forces may take part in strikes on Iran.

In France, President Emmanuel Macron has been clearer that the US/Israel attack is “outside of international law” and that it “cannot approve” of it. That said, officials in Paris have expressed satisfaction with the killing of Khamenei. France announced on March 3 that it will enter the conflict in what it calls a “strictly defensive” manner, deploying its aircraft carrier Charles de Gaulle to the eastern Mediterranean. Following President Trump’s most recent threats against Spain, President Macron expressed solidarity with Spain.

With some exceptions (notably Norway), smaller countries in Europe have also tended to refrain from criticising the US and Israel, stating support for the objectives of their military campaign, leaving aside that the expression of these objectives constantly change. Denmark, for instance – itself recently subject to threats of US use of force to acquire Greenland – spoke  at the UN Security Council emergency meeting about Iran’s “unacceptable behaviour”, condemning its retaliatory action, but did not address questions relating to the legality of US/ Israel military action.

Canada’s Prime Minister Mark Carney – whose speech at Davos in January was seen by many as an attempt to set a fresh agenda to bring back international law in the face of “great power rivalry”, rather than to just “go along to get along” – has also been less than clear that international law matters when it comes to military action against Iran. Noting that “Iran is the principal source of instability and terror throughout the Middle East”, Carney stated support for the US “acting to prevent Iran from obtaining a nuclear weapon and to prevent its regime from further threatening international peace and security”. Carney did not touch on issues of legality, causing dismay among some in Canada, as Mark Kersten explains here. Australia has taken a position similar to Canada’s.

In brief, Spain’s position stands in sharp contrast to responses from most countries in the West which have avoided distancing themselves from the unlawful use of force by the US and Israel in Iran, often implying the general irrelevance of international law in this context. 

Such behaviour undermines the normative force of UN Charter and customary rules prohibiting the use of force, which it is in the interest of all to maintain. This follows a long-lasting, but unfortunate, trend where States in the West insist on the prohibition of the use of force when it comes to the action of its perceived foes, while downplaying the relevance of these fundamental norms in international law when use of force is targeting regimes they dislike. 

That trend is associated with the notion of a so-called ‘rules-based international order’, defined by selective application of the rules of international law and driven by ideas about Western exceptionalism. As Mark Carney said at the recent Davos meeting, the “story of the international rules-based order was partially false” in the sense that the strongest “would exempt themselves when convenient”: international law has been applied in this Western vision of global order with “varying rigour depending on the identity of the accused or the victim”. 

The position taken now by many leaders in the West – including Carney – concerning the use of force against Iran regrettably suggest they are once again falling back in this trap. 

The Sánchez government in Spain is emerging as the strongest voice in the West for the universal application of international law. For that, it should be respected, not lectured as Chancellor Merz did, sitting next to President Trump in a press briefing on March 3. Insisting on the equal application of fundamental rules in international law, regardless of whether that involves perceived friends or foes, is critical not only as a matter of principle, but also for States to appear credible, to act with legitimacy and according to principles of humanity.