Dublin — The specter of an armed Protestant backlash against renewed efforts by Britain and the Irish Republic to resolve their differences is causing considerable alarm here in Dublin.
The Rev. Ian Paisley, Ulster's fiery Protestant leader, has just announced he will lead a series of rallies throughout Northern Ireland to protest what he described as a British sellout. He added he could not rule out the use of force it any attempt was made to force Northern Ireland into union with the Irish Republic.
He recounted the words of Ulster's Lord Edward Carson, who proclaimed after Britain proposed home rule for Ireland in 1920, "Ulster will not be delivered into the hands of its enemies."
The focus of Mr. Paisley's anger is the summit meeting between the British prime minister, Margaret Thatcher, and her counterpart in the Irish Republic, Charles J. Haughey. Mr. Paisley says the agreement reached between Mrs. Thatcher and Mr. Haughey in Dublin last Dec. 8 already has led to both sides moving toward a new constitutional position for Ulster that would lead to a united Ireland.
But in Dublin there is considerable dismay that these so-far-secret meetings between government officials have raised Mr. Paisley's hackles at such an early stage.
The officials are bound by a code of strict secrecy, and they are convinced that at best Mr. Paisley is only guessing at what is being discussed, or at worst has decided to raise Protestant fears in Ulster for his own self- aggrandizement.
In May Mr. Paisley and his Democratic Unionist Party will be trying to oust rival Protestant unionists from Ulster's district councils. The two sides appear to be locked in an internal struggle to capture the majority Protestant vote, and Mr. Paisley seems to want to prove to Mrs. Thatcher that he is the real leader of Ulster's Protestant people.
But with less than 20 percent of the vote, his claim has always looked hollow , and the more moderate Official Unionist Party is the grouping the British government seems to favor dealing with.
Neither side in Ulster is being kept informed as to the agenda of the current Anglo- Irish discussions. Dublin would like to see an informal treaty signed with te British announcing a new era of cooperation over a wide spectrum a of social and economic matters.
On Northern Ireland they would hope a new framework could evolve whereby Dublin had some say about various aspects of life there. But the Dublin government is not thought to be pressing for unification or any alteration of the border between the Irish Republic and Northern Ireland. Mr. Haughey believes, however, that previous attempts at resolving the Ulster deadlock have faltered because the Irish Republic has not been given sufficient say in events there.
He has recently spent considerable time trying to placate Protestant fears. He has been emphasizing the need for reconciliation and the economic benefits that could come Ulster's way from a new agreement with Britain.
But the more Mr. Haughey says, the less Mr. Paisley and his supporters like what they hear. And Mrs. Thatcher's buttoned lip on the subject is grist for his mill.
There is also a feeling in Dublin that Mrs. Thatcher might as well face up to the Protestant threat now, or the current joint-studies exercise may be seriously jeopardized later.
The Dublin government is working toward making firm proposals by midsummer that can be the subject of a special Anglo-Irish meeting in London promised by Mrs. Thatcher to Mr. Haughey at their last meeting.
One senior official commented privately and candidly:
"The problem with Ulster is if we allow a political vacuum to develop, the paramilitaries move in and put the heat on. But when we actually get political progress as now, the same paramilitaries surface and start threatening."