She called it, simply, the worst moment of her life.
It came in March 1982 during the days before the Falklands War, after Argentina established an unauthorized presence on Britain's South Georgia island amid talk of a possible invasion of the Falklands, long held by Britain.
Prime Minister Margaret Thatcher realized there was little that Britain could do immediately to establish firm control of the contested islands, and feared Britain would be seen as a paper tiger that could no longer defend even its diminished empire. She was told that Britain might not be able to take the islands back, even if she took the risky decision to send a substantial armada to the frigid South Atlantic.
"You can imagine that turned a knife in my heart," Thatcher told an inquiry board in postwar testimony that has been kept secret until its release by the National Archives on Friday, 30 years after the events it chronicles.
"No one could tell me whether we could re-take the Falklands — no one," she told the inquiry board. "We did not know — we did not know."
The assessment is more downbeat than the view offered in Thatcher's memoir, "The Downing Street Years."
FILE - In this April 14, 1982 file photo, British Prime Minister Margaret Thatcher leaves her official 10 Downing Street residence in London, for an emergency session of Parliament on the Falklands crisis. She called it, simply, the worst moment of her life. It came in March 1982 during the days before the Falklands War, after Argentina established an unauthorized presence on Britain’s South Georgia island amid talk of a possible invasion of the Falklands, long held by Britain. The vivid picture of Thatcher’s feelings of helplessness and rage, and eventual resolve are portrayed in thousands of pages of formerly Secret documents released by the National Archives on Friday, Dec. 28, 2012. (AP Photo/Bob Dear, File) Close
Thatcher's handling of the Falklands crisis is remembered as one of the key tests of her leadership. The former prime minister, now 87, has been hospitalized since having a growth removed from her gall bladder shortly before Christmas. She has stayed out of the public eye in recent years because of worsening health problems.
Argentina did invade on April 2, and Thatcher launched a naval task force to take back the islands three days later, after the United Nations condemned the invasion. Britain succeeded by mid-June. The war claimed the lives of 649 Argentines and 255 British soldiers, along with three elderly islanders.
Thatcher testified she had been terrified that by sending the seaborne force which would take weeks to reach the Falklands (known as Las Malvinas in Spanish) she would provoke even more aggressive action by the Argentines while the vessels were in transit. She feared this might make the military operation even more hazardous when they arrived.
She persisted in the bold mission despite the risk of an Argentine troop buildup that might force her to turn the armada back, a result that she said "would have been the greatest humiliation for Britain."
She doesn't state the obvious political cost: The mission's failure would have cut short the career of Britain's first female prime minister with her almost inevitable ouster as party leader.
The vivid picture of Thatcher's feelings of helplessness and rage — and eventual resolve — are portrayed in thousands of pages of formerly Secret documents released by the National Archives.
Historian Chris Collins of the Thatcher Foundation — which plans to make the documents available online — said Thatcher's testimony before the inquiry chaired by Oliver Franks was "very carefully prepared" because she felt politically vulnerable.
"She was concerned at the damage the report might do her, because there was much potential for embarrassment at the government's pre-war policy of trying to negotiate a settlement with Argentina ceding sovereignty while leasing back the islands for a period, plus suggestions that Argentine intentions could have been predicted and invasion prevented," he said.