Ireland's four leading nationalist politicians are meeting in Dublin this week to begin to hammer out an agreed plan for a new Ireland. By St. Patrick's Day, March 17, they hope to produce a blueprint that will appeal to both the British and Irish governments.
Most important and most difficult, they would like to come up with a proposal that would not be totally repugnant to the 1 million Northern Ireland Protestants who so far have refused to consider any form of united Ireland.
The four leaders make up the steering committee of the New Ireland Forum, which held its first meeting last May. Its chairman is Galway University professor Colm O'Heocha.
The forum consists of the three main southern Irish parties, plus the Belfast-based Social Democratic and Labour Party, which represents Ulster's half million Roman Catholics and favors Irish unity.
The leaders - Irish Premier Garret FitzGerald, opposition leader Charles Haughey, Labour Party leader Dick Spring, and SDLP leader John Hume - face three options:
* A united Ireland incorporating the north and ruled from Dublin.
* A federal Ireland with north and south having a large measure of autonomy but ultimately responsible to Dublin.
* Joint sovereignty with Britain and Ireland assuming control over the north.
The crucial test facing the forum is to produce an agreed blueprint. Mr. Haughey, the hawkish leader of opposition Fianna Fail, has long favored straight unity with the best terms possible for northern unionists once they accept such a deal.
Mr. FitzGerald, the donnish and moderate leader of Fine Gael, is thought to favor joint sovereignty. So does Mr. Hume, the articulate and persuasive Derry Catholic who is the acknowledged architect of the forum project.
It is thought that in any compromise plan straight unity will be ruled out, joint sovereignty favored, and a federal Ireland produced only as a fallback.
Significantly, Hume has already talked to British Prime Minister Margaret Thatcher. He denied he had put forward any plan for joint sovereignty and pointed out that a final blueprint had not been produced. But it is clear the British are being kept informed at the highest level.
Realistically the British reaction to any plan will be influenced by Northern Protestant reaction. This has been predictably hostile.
Peter Robinson, deputy leader of the Rev. Ian Paisley's Democratic Unionists said, ''Unionists do not intend to dilute their constitutional position or the authority of the realm of their country. John Hume will have to try again.''
Oliver Napier, leader of the middle-of-the-road Alliance Party, summed up with his typical lawyer's precision, ''No constitutional jiggery-pokery will solve anything. The root of unionist resistance is the belief that as a community they will cease to exist in a united Ireland.''
The Northern Protestant politicians who want to maintain the union with Britain refused to talk to the forum. But individual northerners and some groups from the Protestant churches have done so. They have warned repeatedly that Northern Protestants do not want unity.