By far Britain’s least favourite American during the Falklands War was the US Ambassador to the UN, Jeane Kirkpatrick.

Only hours after the 1982 invasion of the Falklands she notoriously attended as guest of honour a reception at the Argentine Embassy in Washington. She then went on television to assert that if the islands rightly belonged to Argentina its action could not be considered as “armed aggression”.

Her efforts to tilt the Reagan Administration in favour of Argentina and against Britain provoked a most undiplomatic row with the US Secretary of State, Alexander Haig. Haig charged that Kirkpatrick was “mentally and emotionally incapable of thinking clearly on this issue because of her close links with the Latins”.

Kirkpatrick dismissed Haig’s policy as “a boy’s club vision of gang loyalty”. She accused him of being blindly pro-British and said that he and his advisers were “Britons in American clothes”.

Kirkpatrick, who was close to the Argentine junta headed by General Galtieri, argued that America should not jeopardise its relations with Latin America by supporting Britain in a colonial war. Haig and the US Defence Secretary Caspar Weinberger (obituary, March 29, 2006) took Britain’s side, and Weinberger was later awarded an honorary knighthood for his role in the victory.

Had Kirkpatrick prevailed, Britain would have been deprived of American fuel, Sidewinder missiles and other arms, and the vital US satellite intelligence that enabled it to win the war. And Galtieri and his junta would not have been replaced by a freely elected government.

President Reagan found himself in the midst of the tug-of-war between the West’s two most formidable conservative women — Jeane Kirkpatrick and Margaret Thatcher.

Thatcher prevailed, but though the two shared a similar ideology, the British Prime Minister never forgave Kirkpatrick for her role in the Falklands.

Kirkpatrick first came to Reagan’s attention on the eve of his first Administration over an article she had written for Commentary, a publication backed by the American Jewish Committee. Entitled Dictatorships and Double Standards, it argued that right-wing “authoritarian” governments, such as those in Argentina, Chile and South Africa, suited American interests better and were “less repressive” than pro-Soviet “totalitarian” regimes. She castigated the emphasis placed on human rights by the previous, Carter Administration and blamed it for undermining right-wing governments in Nicaragua and Iran.

Overnight Kirkpatrick, a not particularly well-known academic and political scientist, and a paid-up Democrat, became one of the most powerful women in America as Ambassador to the UN with a seat in the Reagan Cabinet and a member of the National Security Council.

As the US Representative to the UN for four years after the 1980 election, she came to be regarded as the ideological conscience of the Reagan Administration. Combative and confrontational, she symbolised the assertiveness that characterised American foreign policy after Reagan took office. She declared at the time: “I am not a professional diplomat. I’ve not signed over my conscience and intellect.”

Adored by the neoconservatives and despised by the liberal foreign-policy establishment, she provided the intellectual foundations for a policy which aimed to confront Soviet expansionism and restore US preeminence in world affairs. She endeared herself to Reagan by lecturing Third World nations that the US would no longer put up with the sort of abuse it had suffered during the Carter Administration.

Many of her fellow ambassadors found her abrasive and uncompromising, but for others she was a refreshingly cold blast through the cynical corridors of the UN, attacking hypocrisy and the double standards of the Third World. She was a formidable figure with cropped hair, a jutting lower lip and a growl in her voice.