Margaret Thatcher never gave the Secretary of State for Northern Ireland role to anyone with a promising political future, the files claim.
The former Prime Minister is said to have always opted for what was described as an "unspectacular appointment" - one designed to "keep things ticking over" in Northern Ireland.
Irish State papers revealed that top officials in the Government said Mrs Thatcher had only modest expectations of improving the situation in Northern Ireland in 1988. In July of that year, during a lunch between Ferdinand Mount - a former head of the Policy Unit at No 10 - and an Irish government official, Mrs Thatcher's position on Northern Ireland was discussed.
After the meeting, the Irish government official wrote to Dermot Gallagher, then the assistant secretary at the Anglo-Irish Division, to outline the main points which had been raised during the meeting.
He said: "The Prime Minister, however, has never focused for very long on the Northern Ireland problem, despite the assiduous efforts of (Thatcher's adviser Charles) Powell and (Peter) Utley over the years to interest her in it."
According to the documents, which were released under the 30-year rule, Mr Mount, who was described as a "noted right-wing journalist", worked on domestic and economic issues, but he also had a strong interest in Irish affairs.
He told the Irish official that Mrs Thatcher had "very modest expectations" about her chances, or any other Prime Minister's chances, of bringing about a "fundamental improvement of the situation" in Northern Ireland.