She had two great allies in the endeavor. Ronald Reagan, who was initially hesitant to risk damaging relations with Argentina. As recounted by Bob Woodward, Argentina was helping to train the anti-communist Nicaraguan Contras in Honduras. Reagan eventually gave in and not only publicly supported the UK's policy, but according to Woodward, covertly provided intelligence to Thatcher.
The other ally was a man she personally came to the defense of in a 1999 speech:
President Pinochet was this country's staunch, true friend in our time of need when Argentina seized the Falkland Islands. I know - I was Prime Minister at the time. On President Pinochet's express instructions, and at great risk, Chile provided enormously valuable assistance. I cannot reveal all the details. But let me mention just one incident.
During the Falklands War, the Chilean airforce was commanded by the father of Senator Evelyn Matthei, here with us tonight. He gave us early warning of Argentinian air attacks, which allowed the task-force to take defensive action. The value of this intelligence was proved by what happened when it stopped. One day, near the end of the conflict, the Chilean long-range radar had to be switched off for overdue maintenance. That same day - Tuesday 8th June, a date etched on my heart - Argentinian planes attacked and destroyed the Sir Galahad and Sir Tristram landing ships, with heavy casualties.
Altogether, some 250 members of our armed forces lost their lives during the Falklands War. Without President Pinochet, there would certainly have been many more. We all owe him - and Chile - a great debt.
Wise move on Pinochet's part, because the desperate Argentine junta had their sites set on Chile if the Falklands went smoothly.
What does this have to do with Iran's quest for Nuclear Weapons? Ask Miguel Angel Toma, the former head of the Argentina's intelligence service
So basically, because of the Falklands war and the Argentine return to democracy, Iran can't do what Maggie threatened to do to Buenos Aires.