"Ireland is a neutral country, we're militarily non-aligned, but we are certainly not neutral on an issue like this, when there is blatant aggression happening on the continent of Europe."

The words of Simon Coveney, the Minister for Foreign Affairs, speaking on RTÉ's Morning Ireland in the hours after Russia launched its invasion of Ukraine.

Neutral - but not neutral.

Some eyebrows might have been raised at this formulation, but in fact, it fits into Ireland's long tradition of nuanced neutrality.

A strict interpretation of neutrality requires a state not just to stay out of a war, but to be completely impartial towards the belligerents.

But Ireland has often been partial towards one side in a conflict. This has partly been determined by our proximity to Britain, partly to our self-identification as part of the "West", and partly due to our opposition to states that break international law.

Even before independence was achieved, Éamon de Valera recognised that we would have to take account of British security concerns.

As far as London was concerned, Ireland and Britain formed a strategic whole. De Valera recognised this and was prepared to offer guarantees that Irish territory would never be used to mount an attack against Britain.

This limited Ireland's options in foreign policy. But there was a flip side. There was no need for Ireland to build a real defence capability because it could rely on the Royal Air Force and the Royal Navy to defend Irish airspace and territorial waters.

And, as the recent report of the Commission on Defence made clear, it still does.

After he came to power in 1932 - and became his own Minister for External Affairs - De Valera was a keen supporter of collective security, through the League of Nations (the forerunner of the United Nations).

Éamon de Valera (2nd from right at long table) at the League of Nations in Geneva in September 1932

He believed the only protection for small powers lay in international law. States that flouted the rules, no matter how powerful, must be severely punished. He therefore strongly supported sanctions against Italy after Mussolini invaded Ethiopia. However, it quickly became clear that Britain and France had no appetite for taking real action, allowing Mussolini to get away with aggression.

In one of the best speeches of his lengthy political career, de Valera confessed to "a feeling of bitter humiliation" as he addressed the League of Nations in Geneva: "Is there any small nation represented here which does not feel the truth of the warning that what is Ethiopia's fate today may well be its own fate tomorrow?"

Collective security having failed, the only option for a small state like Ireland was to try to stay neutral in the major war that now seemed inevitable.

Of course, staying out of World War II would prove difficult if Britain held on to the three Irish ports it held under the terms of the 1921 Treaty, in Cobh, Berehaven and Lough Swilly. By agreeing to return the ports, British Prime Minister Neville Chamberlain made Irish neutrality possible.

In return, de Valera took account of British concerns, telling the German Ambassador days before war broke out that because of geography he would have to show "a certain consideration for Britain".

A strict interpretation of neutrality requires a state not just to stay out of a war, but to be completely impartial towards the belligerents

And he did – Ireland supplied Britain with food and manpower, cooperated on plans to repel a German invasion, gave intelligence assistance, and supplied vital weather information. This help to the Allied cause was overshadowed at the very end of the war by de Valera's foolish decision to follow the letter of neutrality and visit the German Ambassador to offer condolences on the death of Hitler. This led to a storm of criticism, and made Irish neutrality seem stricter than it really was.

But earlier in the war, de Valera had been prepared to stray from strict neutrality. In May 1940, he criticised the German attack on fellow neutrals Belgium, Luxembourg and the Netherlands: "I think I would be unworthy of this small nation if on an occasion like this I did not utter our protest against the cruel wrong which has been done them."

In the context of the time, with a German attack on Ireland all too possible, these words demonstrated that Ireland's nuanced neutrality did not extend to condoning unprovoked aggression.

So, Ireland emerged from World War II as one of only four European states that had remained neutral throughout (the others being Sweden, Switzerland and Franco's Spain). But would it remain neutral in the Cold War to come?

The fact that it did was not because of an attachment to neutrality. Successive Irish governments made it abundantly clear that they opposed the Soviet Union.

But when the invitation came to join the talks that led to the formation of NATO in 1949, the Inter-Party Government led by John A Costello tried to use neutrality as a bargaining chip.

The reply to the invitation stressed that Ireland agreed with the general aim of the proposed alliance and was opposed to Communism and attached to democracy and Christianity.

The stumbling block, it said, was partition, as it could not join a military alliance "with the state that is responsible for the unnatural division of Ireland". The then Minister for External Affairs Seán MacBride thought that Irish membership of NATO was so important to the Alliance that the Americans would put pressure on London to end partition.

The first session of the North Atlantic Council - the principal political decision-making body of NATO - in Brussels in September 1949

In fact, as long as NATO had bases in Northern Ireland, it could do without the rest of the island, and the Irish reply was simply ignored. MacBride had overestimated Ireland's strategic importance - and his own diplomatic skills.

Much later, Charles Haughey indicated to Margaret Thatcher that he would be prepared to join NATO if there was movement towards a united Ireland (Mrs Thatcher was no more attracted by this trade-off than her predecessors in 1949).

Haughey's Minister for Foreign Affairs, Brian Lenihan Senior, was even more forthcoming in a discussion with a British diplomat in 1980. While "the public would have to be educated", he thought NATO membership was sure to come. "In his view, the Republic's neutrality was diminished as soon as it joined the EEC."

Non-membership of NATO had indeed become an issue when Ireland was seeking to join what was then the European Economic Community in the 1960s.

Taoiseach Seán Lemass made no bones about his view. In September 1962, he told journalists: "We do not wish in the conflict between the free democracies and the Communist empires to be thought of as neutral. We are not neutral and do not wish to be regarded as such."

While Ireland remains outside any military alliance such as NATO (above), there is a clear tradition of Irish foreign policy that supports democracy and opposes breaches of international law

His successor, Jack Lynch, told the Dáil in July 1969 that if Ireland were admitted to the EEC, "we would naturally be interested in the defence of the territories embraced by the Communities. There is no question of neutrality there."

Twelve years later, then-Taoiseach Charles Haughey said that while Ireland was not a member of any military alliance, it stood for certain values. "Our place is with the Western democracies, and we share common concepts of human rights, freedom under the law, individual liberty and freedom of conscience. Our economic interests also are tied in with the Western industrialised world. We are, therefore, neither ideologically neutral nor politically indifferent... In the event, therefore, of the European States being organised into a full political union, we would accept the obligations, even if these included defence."

Of course, Ireland is no longer the only neutral in the European Union, having been joined by Sweden, Finland and Austria, and moves towards a common defence remain controversial. Guarantees of continued Irish neutrality were vital to the acceptance – on the second time of asking – of the Lisbon and Nice Treaties in referendums.

But while Ireland remains outside any military alliance, there is a clear tradition of Irish foreign policy that supports democracy and opposes breaches of international law. The reaction to the Russian invasion of Ukraine lies firmly in that tradition.

Neutral - but not neutral.

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