YESTERDAY marked the 70th anniversary of the American Note demanding the expulsion of Axis diplomats from Ireland on the grounds that they supposedly posed a threat to the forthcoming Allied invasion of Europe. The whole thing was responsible for one of the greatest distortions in Irish history.

The note really had nothing to do with security; it was a deliberate ploy to generate the impression that taoiseach Éamon de Valera was indifferent to the plight of British and US servicemen. Consequently, the true nature of this country’s wartime policy has been seriously distorted ever since.

In 1970, when I began research on a doctoral dissertation on Irish neutrality, J Russell Forgan, deputy director for Europe of the Office of Strategic Services (OSS) — the forerunner of the CIA — assured me there was extensive secret co-operation between the Irish and the OSS. “The Irish worked with us on intelligence and security matters almost as if they were our allies,” he wrote. “They have never received the credit due them.

“I doubt that in the last year of the war there was an Axis spy in Ireland that the Irish and ourselves did not know about.” Forgan added. “Most of them were ‘doubled’. By that, I mean that they worked for us and sent their so-called superiors news which we fed them. In that respect, they were very helpful to our cause.”

Colonel Dan Bryan, head of Irish Military Intelligence (G2), suggested this was an exaggeration. “Forgan is wrong,” Bryan stated. “There were no double agents in Ireland.”

The German minister and his staff in Dublin were effectively being used as virtual double agents, but did not realise it. All of the German agents sent to Ireland as spies were uncovered. None worked as a double agent in the 26 counties, but there was one agent that nobody talked about for another quarter of a century.

The Germans had dropped Joseph Lenihan — an uncle of Brian Lenihan and Mary O’Rourke — as a spy over Meath in July 1941. With G2 hot on his heels, Lenihan slipped across the border and offered his services to the British as a double agent. He worked for MI5 under the codename “Basket” for the rest of the war. But the British have still not released their files on him.

After the US joined the war in December 1941, the OSS stationed three undercover agents in Ireland. The first was Ervin “Spike” Marlin, officially supposed to be economic adviser to David Gray, the US minister to Ireland. Marlin was an American who had studied at Trinity College Dublin from 1929 to 1932.

One of his first tasks for the OSS was to assess the sympathies of Irish politicians. He reported that three Fianna Fáil deputies were pro-German: Backbenchers Dan Breen and Tom McEllistrim, and Patrick J Little, the minister for posts and telegraphs.

As this report was being transmitted in the diplomatic bag, Gray insisted on reading it, then demanding to know Marlin’s source for the information on Little. Marlin reluctantly told him it was Erskine Childers — then a junior minister and a future president of Ireland. A few days later, Childers complained to Marlin that Gray had not only protested about Little being pro-German, but had gone on to commit the appalling indiscretion of naming Childers as the source of this information.

Realising that Marlin was an OSS agent, Joseph P Walshe, the secretary of the Department of External Affairs, offered that Irish security would co-operate with the OSS through Marlin. Walshe had already arranged a similar set-up between G2 and Britain’s MI5. But Gray opposed such co-operation as he was deeply suspicious of Walshe.

Although Gray had no prior diplomatic experience, he enjoyed considerable political influence because he had direct access to the White House as he was married to an aunt of the first lady, Eleanor Roosevelt. The OSS soon became painfully aware that his political clout was not matched with good judgment.

In a post-war memoir published for the first time in 2012, Gray contended that he had better sources of information in Ireland than the OSS. He did not identify those sources in the memoir, but his letters to US president Franklin D Roosevelt reveal they were from another world.

A strong believer in spiritualism, Gray was passing on advice to the president from supposed ghosts. He informed Roosevelt, for instance, that the ghost of late British prime minister Arthur J Balfour had informed him during a seance on November 8, 1941, that Walshe was “a leading quisling” and that he “is hand in glove with the German Minister”.

At another seance on December 2, 1941, the ghost of the late president Theodore Roosevelt supposedly belittled the danger of a Japanese attack on US forces. This was the Tuesday before the Japanese attacked Pearl Harbor, but Gray never doubted that he was in contact with the ghosts.

“Four days after this communication,” Gray wrote to FDR, “the Japs attacked Pearl Harbor. They had T.R. fooled. I suspect that if these communications come through pretty much as given our friends on the other side don’t know very much more than they did on this side.”

Despite Gray’s objections, the OSS accepted Walshe’s offer to co-operate with Marlin, G2 turned over voluminous reports on German spies already captured, as well as the names and addresses of people in the US to whom German nationals living in Ireland, or pro-German Irish people, were writing. Over 4,000 people were named.

Gray was so sour over the co-operation that the OSS decided to move Marlin in London, from where he would travel back to Dublin when necessary. G2 kept in contact with him with regular reports that were sent to London through the Department of External Affairs in the Irish diplomatic bag.

Walshe was so co-operative that Marlin suggested the Irish would possibly use their diplomats on the continent to collect information for the OSS. R Carter Nicholas, the head of the Éire Desk at OSS headquarters in Washington DC, visited Dublin to explore this possibility in September 1943.

Nicholas reported that he asked Walshe about “the possibility of our receiving information from Irish diplomatic sources. It was intimated that other neutrals had gone as far.”

With de Valera’s approval, Walshe acceded to the request, and he read excerpts from reports from Irish diplomats on the continent in which Nicholas and Marlin might be interested. He also agreed to transmit to the Irish chargé d’affaires in Berlin “a request for information on the political situation in Germany at the top”.

In the following weeks, Marlin supplied questions to Walshe for the respective Irish representatives in Berlin, Rome, and Vichy. Walshe asked the questions of the respective diplomats and then forwarded their replies to Marlin. In effect, Irish diplomats were being used as US spies. Gray was far from satisfied.

He returned to the US and met Roosevelt and Winston Churchill on August 16, 1943. He persuaded them to ask for Irish bases as a means for discrediting de Valera to ensure he would not cause difficulties between the British and US over partition after the war.

Gray did not want Irish bases; he just wished to provoke de Valera’s refusal. He suggested, for instance, that the request should stress the bases were no longer needed but the Allies were just offering Ireland a chance to share in the forthcoming victory.

de Valera had already been so helpful that the US joint chiefs of staff thought he might actually accede to the request, and they warned that Irish bases would be worse than useless. They would be a liability to the Allied war effort, which was what de Valera had been claiming for years.

The idea of requesting bases was therefore blocked, but Gray came up with another suggestion. He proposed Roosevelt ask the Irish government to expel the German and Japanese representatives from Ireland because they supposedly posed a threat to the forthcoming D-Day invasion of Europe.

-Ryle Dwyer’s Behind the Green Curtain: Ireland’s Phoney Neutrality during World War II, published in paperback by Gill & Macmillan.

On Monday: How the German minister and his staff in Dublin were effectively used as double agents.