Belfast builds its own `Berlin Walls'. Both Protestant and Catholic areas welcome such barriers to violence

Political graffiti shout from blackened brick buildings. Barbed wire rolls endlessly across the tops of shops and government offices. Armored vehicles suddenly careen around corners. This drab and depressing urban landscape is as much part of the Falls Road, a Roman Catholic bastion, as it is of the Shankill Road, a Protestant area. It is the churches -- and the daubed political slogans -- that help a visitor tell them apart.

These two working-class districts, gripped in the past by sectarian violence, have something else in common: the 20-foot-high barrier more than 300 yards long that separates them. Similar barriers have been built elsewhere in Belfast.

What makes these Belfast walls different from their more notorious counterpart dividing East and West Berlin is that in Belfast people on both sides want them. They are a protection against the violence that is always seen to come from the other side.

The Belfast walls that separate communities are symptomatic of a political divide that has frustrated all attempts to resolve Northern Ireland's problems.

Although the communal violence that was a nightly occurrence in the Shankill and Falls Road in the early 1970s has virtually vanished, the political stalemate persists. In some respects, the alienation is more marked.

Even at universities where a wide range of political opinions might be expected, the situation is polarized. According to history student Catherine Thompson, who attends the handsome, mellow-bricked Queen's University in a more gracious part of Belfast:

``There's no middle ground. You're either unionist [favoring union with Britain] or nationalist [favoring ties with the Catholic-dominated Irish Republic].'' On the national scene, she sees only intransigence among leaders: ``No one is willing to give in . . . not an inch.''

Such sentiments are shared by Prof. Cornelius O'Leary, head of political studies at Queen's. He describes as intransigent all three major political leaders -- James Molyneux, Protestant leader of the Official Unionist Party; the Rev. Ian Paisley, leader of the more hard-line Democratic Unionist Party; and John Hume, leader of the largely Catholic Social Democratic and Labour Party (SDLP).

Back in '70s, Professor O'Leary says, the then Unionist and SDLP leaders, Brian Faulkner and Gerry Fitt (now Lord Fitt), realized ``the only way to get out of the morass is to sit down together.'' Today, he says, Mr. Faulkner's successors ``have retreated into their laager [South African-style stronghold]'' and Mr. Hume has taken a much harder line than Lord Fitt did.

The refusal of the leaders of the major parties to hold talks has exasperated Douglas Hurd, Britain's secretary of state for Northern Ireland, who proposed them.

The divide between the political parties in Northern Ireland is perhaps wider than ever, but relations between Ireland and Britain have seldom, if ever, been better. Not since partition in 1921 has any Dublin government been as well disposed toward London as the government of Garret FitzGerald, despite a rebuff after last fall's summit. Nor has any government been as understanding of the views of the Protestant majority in the north.

Circumstances have helped pull Dublin and London closer together. Both governments recognize an imperative mutual need to extinguish the Provisional wing of the illegal Irish Republican Army (IRA), particularly after the IRA mortar attack on Feb. 9 that killed nine policemen in Newry, close to the Irish border.

But the Irish government's willingness to help put the screws to the IRA has forced Britain to be sensitive to nationalist aspirations within Northern Ireland. Hence, an Anglo-Irish consensus that this northern nationalism be kept within constitutional bounds, as represented by the SDLP, rather than being hijacked by the IRA and its political partner, Sinn Fein.

This consensus translates into encouragement of a power-sharing role for the SDLP, a greater recognition of the northern Catholics' nationalist identity, and a role for the Irish Republic that would allow it influence in Northern Ireland affairs.

Moves to formalize this ``Irish dimension'' have the support of three of the four principal parties: the Irish Republic, the British government, and the SDLP as the recognized standard bearers of moderate Northern Irish nationalism. But the Protestants in Northern Ireland are left feeling distinctly uneasy. And the IRA rejects such moves, because they leave the British in control.

Some moderate Protestants feel frustrated because, despite civil-rights reforms and substantial housing improvements, Catholic political opinion has hardened rather than moderated. This, it is feared, plays into the hands of Protestant extremists.

Such extremists had argued when the ``troubles'' began in 1969 that civil rights agitations were more a nationalist ploy to undermine Northern Ireland than a legitimate means to redress grievances on housing and discrimination.

While Unionists view the IRA as an out-and-out terrorist organization, many of them do not readily embrace the SDLP either. ``It's hard for us living in this place to see [John] Hume as moderate,'' says A. T. Q. Stewart, reader in modern history at Queen's University and author of several books on Northern Ireland.

Mr. Hume's decision that representatives of his party should not take their seats in the Northern Ireland Assembly angered many Protestants who feel he has abandoned the search for an internal solution in favor of the Irish dimension. Political observers suggest that the growing electoral challenge that Sinn Fein presents to the SDLP makes Hume reluctant to be seen operating within the existing political system.

At the same time Hume defenders, and they include moderate politicians in the south, feel he has not been given enough credit for upholding the democratic process. Hume has always insisted that unification can only come through the consent of the majority in the north.

In an interview in his power base at Derry, Hume says: ``As far as I am concerned the differences between Sinn Fein and myself are very fundamental as long as they are wedded to a policy of violence -- because their violence is mainly why the problem is a lot worse.''

The promotion of Hume's SDLP by both Dublin and London makes Unionists highly suspicious: they feel it is being done at their expense.

A common Protestant evaluation of the British government's attitude to them is: ``We've given you constitutional guarantees. Now try to be conciliatory.''

A leading Unionist, Robert McCartney, insists that as Unionists, ``We would be prepared to give, but not on the constitutional issue.'' He has been instrumental in drawing up a bill of rights. But he fails to see how ``political aspirations for a united Ireland can be a human right that has to be catered for.''

Britain and Ireland are increasingly moving in tandem toward a political framework no longer strictly confined to Northern Ireland, a framework that would no longer automatically accord the Unionists a veto. Instead Dublin and London appear to be concentrating on the wider problem of relationships -- not just within Northern Ireland, but with Ireland as a whole, and between Britain and Ireland, in which any agreement will not be subject to veto. That's what worries Unionists.