Maybe the fact that the more she turned the security screw on Irish terrorism, the more barbaric it became served to convince politicians who came after her that there must be a better way of bringing peace to Northern Ireland.
As we await the lady's last farewell through the streets of London on Wednesday, we are left to reflect on her legacy to this part of her cherished United Kingdom.
Margaret Thatcher's attitude to Northern Ireland was so single-mindedly succinct that it could have been written on the back of a cigarette packet.
"I started from the need for greater security, which was imperative," she confessed in her autobiography. "If this meant making limited political concessions to the south, much as I disliked this kind of bargaining, I had to contemplate it."
Ideally, she saw Stormont run along the same lines as Westminster, with majority rule and safeguards for minority interests. She accepted power-sharing as an alternative only because she was sufficiently convinced that nationalists would not buy her first preference.
She failed to find any solution to the conflict here because her approach was unduly simplistic, a far cry from the Good Friday Agreement.
She failed because the IRA was still intent on a victory it could not achieve. She failed, too, because the democratic parties in Northern Ireland had not even begun to fathom how far each would have to travel to reach agreement.
She failed because she lost patience with people who did not agree with her – hardly an attribute for someone trying to find answers and solutions in such a divided society.
My memories of her time in office relate to the secretaries of state she employed in Belfast, the duties she expected them to conduct and the relationship she had with them – not always cordial.
Her heart was rarely in any of the political initiatives her ministers in Belfast pursued. There was Humphrey Atkins – unkindly nicknamed 'Humphrey Who?' because of his low profile and soft-spoken manner.
She consigned the avuncular James Prior to the Northern Ireland job to face the hunger strikes of 1981 after he had overseen the passage of her major industrial relations reforms through parliament.
He had an uncomfortable relationship with her – especially as she regarded him as one of the 'wets' in her Cabinet.
Then came Douglas Hurd, dry and clinical, whose Foreign Office background may have persuaded Thatcher to sign the Anglo-Irish Agreement against her better judgment, and then Tom King, who suffered the wrath of the unionist Ulster Says No campaign.
I was told that Thatcher was particularly enraged by a headline in the unionist News Letter at that time, which headlined King as 'King Rat'.
Secretaries of state struggled to impress on her the complexity of politics and attitudes here. They toiled under the reality that she had a mind of her own and that she was often impatient and dismissive of the efforts and opinions of local political leaders and parties.
In the end, her appointment of Peter Brooke in 1989 signalled the failure of the limited political initiatives she had tried. We know now that, around that same time, the IRA had begun to look more seriously at an alternative to violence.
Thatcher had thrown everything at the IRA and they had thrown everything back at her. All her efforts to bring terrorism to heel had not worked, but no matter how close the IRA came to killing her, neither the British, nor the unionist, will could be broken.
The decade of the 1980s took the brutality to a new level – from the Grand Hotel in Brighton to the cenotaph in Enniskillen.
Margaret Thatcher's legacy to Northern Ireland may be that, in confronting violent Irish republicanism in the way that she did, in refusing to concede to its demands even though she almost lost her own life in the Brighton bombing, the message got through emphatically that terrorism, of itself, was no answer.
Maybe a Margaret Thatcher confronting the IRA at its most murderous in the 1980s was what it took to bring all of us to our senses in the 1990s and prompt the politicians here to sign-off on the 1998 Good Friday Agreement.