The first was a characteristically blunt refusal to bow to the demands of IRA prisoners that they be given political status. The second was an uncharacteristic act of statesmanship for which she is given little credit.
In 1981, IRA men at the Maze prison escalated their protests from wearing only blankets and smearing their cells with excrement to launching a hunger strike led by Bobby Sands.
"Crime is crime is crime; it is not political," was the Iron Lady's response. Terrorists were simply murderers and should be treated as such, she argued. But the republicans believed they were fighting a war against military occupation and the fact that they were prepared to die for their political beliefs transformed them into heroes even among previously moderate nationalists.
Ten of the hunger strikers starved to death and anger at Britain's intransigence boiled over on to the streets and in the ballot box. Sands was elected to Parliament before he died, and two other hunger strikers became members of the Dail in Dublin. This picture was taken in 1981 after a group of demonstrators in Belfast hijacked a car, parked it at the entrance to a British barracks and set fire to it. As the army moved in, the protesters threw gas bombs at them.
The Troubles started in 1968 when Catholic civil rights activists and republicans began peaceful demonstrations. They were demanding an end to discrimination against Catholics in housing and employment and the inroduction of universal suffrage in local elections - which wasn't granted until 1969. The marches led to clashes with Unionist counter-demonstrators and British troops were sent in to restore order.
The 1981 hunger strikes radicalised nationalists once more and made Sinn Fein, the political wing of the IRA, a powerful political force that threatened to overtake the moderate SDLP as the voice of Catholics.
Herself the target of an IRA bomb in Brighton in 1984, Mrs Thatcher could have been dismissive of nationalist aspirations. Yet the woman who fought a war in the Falklands on the pledge that Britain would never surrender sovereignty did just that by signing the Anglo-Irish agreement with the prime minister of the Irish Republic, Garret Fitzgerald, in 1985.
When I asked how he persuaded her to take such a leap, Mr Fitzgerald said he convinced her that the concept of alienation "was not something dreamed up by socialists but was first used by George Eliot in Middlemarch", and was therefore acceptable for her to take on board.
The agreement gave the Dublin government a limited say in the affairs of Northern Ireland and the right to raise issues of economic and social injustice for the province's Catholics. It paved the way for the Good Friday agreement and peace accord, which could finally install in Northern Ireland a system of government that makes everyone feel included.
Web links BBC reports on the search for peace: http:news.bbc.co.ukhienglishstaticnorthern_irelandunderstandingdefau lt.stm The Irish Times overview of The Troubles: www.ireland.comspecialpeacetroubles Images of political murals from both sides: http:cain.ulst.ac.ukbibdbsmuralsmurals.htm