Since the early nineteenth century Irish-Americans have sought to persuade the White House and Congress to intervene in the politics of Ireland and, after Partition, Northern Ireland. On all occasions they were singularly unsuccessful. There were three reasons for this failure. First, the White House claimed not to intervene in the internal affairs of another sovereign country, a principle of international relations often honoured more in the breach than in the observance by successive US governments. In the case of the United Kingdom, however, it was invariably honoured. In the nineteenth century and until the outbreak of the Second World War, the British Empire was the largest in the world and, following the Second World War, Britain with its ‘special relationship’ was the United States’ most important NATO ally. When questioned about Northern Ireland, the White House religiously echoed the refrain of ‘non-interference in the internal affairs in another country’ and generally supported British policy in Ireland and, later, in Northern Ireland.

The second reason was that initiatives taken in Congress, mainly in the House of Representatives, were unsuccessful. In the early 1980s several attempts at legislative action were made by members of the Ad Hoc Congressional Committee for Irish Affairs, supported by the Irish National Caucus. They failed because successive speakers of the House and leaders of the Senate controlled the business on the floor of each House and they saw to it that no progress was made on the bills. Particularly in the period following the Northern Ireland civil rights agitation, initiatives on the Hill were blocked as a result of extensive lobbying by the British and Irish embassies and pressure from the White House. John Hume, the leader of the SDLP, who was hostile to the MacBride campaign, decisively influenced Speakers Tip O'Neill and Tom Foley. It was not until 1995 that the affairs of Northern Ireland were subject to an official hearing in the House of Representatives before the Committee on International Relations. It was paradoxical that the hearings were held when the Republicans were in control of the House and not the Democrats, the traditional supporters of the Irish cause. The chairman of the committee, the Republican congressman Benjamin Gillman, was a long-standing member of the Ad Hoc Committee.

The third reason for failure was the almost incestuous relationship that existed between the US state department and the British Foreign Office.