Bobby Sands, the convicted Catholic Irish nationalist and recently elected British member of Parliament, lapsed into a coma this morning on the 64th day of his hunger strike in the Maze prison of British-ruled Northern Ireland.

"My son is dying," his mother, Rosaleen Sands, told reporters outside the prison. "I want to appeal to the people to remain calm and have no fighting or deaths. My son has offered his life to improve prison conditions and not for death and destruction."

Sands, 27, a member of the outlawed Provisional Irish Republican Army serving 14 years for a weapons charge, began his hunger strike March 1 to press for political-prisoner status and was later joined by three other inmates who also are still refusing to eat.

His hunger strike has once again attracted the world's attention to the unending sectarian conflict here. From the back-to-back Protestant and Catholic ghettos of west Belfast to the green rolling hills of the Northern Ireland countryside, fears are widespread that Sands' death will prompt an upsurge of violence.

"It's not Bobby Sands really. He just puts the focus on the real problem," said a senior British official when talking about efforts by the government since the latest "troubles" began in 1969 to bring peace to the province. "Whatever we've been doing during the past 12 years, we've arrived at a point which Catholics and Protestants are further apart than ever."

This can be most easily seen in the streets of cramped Victorian row houses and public housing projects of west Belfast, where Catholics and Protestants have completely segregated themselves since 1969. They are separated by "peace lines" that resemble the Berlin Wall.

In many places, the barrier is ugly corrugated steel topped by barbed wire. In others, it is a high brick wall, a street of bricked-up abandoned row houses or a desolate, debris-strewn no-man's land where the buildings were bombed or burned out years ago.

On many walls, the graffiti of hate marks territory claimed by Catholic and Protestant paramilitary.

Contributing to the atmosphere of a war zone are the corrugated steel and barbedwire forts around police and British Army posts, the gray, tank-like Rovers in which police patrol and the road blocks manned by British soldiers, their rifles always at the ready, searching for terrorists.

For days now, the Catholic ghettos have been littered with debris from nightly ritual attacks on the armored vehicles by youths who build street barricades with trash. Even when the atmosphere is not so tense, the security forces, determined to demonstrate aggressively that they will not allow Irish nationalists to establish areas off limits to Protestants, are regularly stoned by small children.

For this generation of children, there has been only segregation, violence, fear and heightened prejudice of 12 years of "troubles." They learn from an early age the litany and legend of sectarian strife going back centuries here and how to distinguish Protestant from Catholic by differences in accent, dress and habit indistinguishable to outsiders. Added to this are vivid memories of the bloodshed and destruction that began in 1969, with each side blaming the other for atrocities real and imagined.

"I don't see how it can ever change," said Betty MacMillan, a Protestant living on the sectarian divide along Springfield Road in west Belfast. "My young ones have known nothing else but the troubles."

Her family, like so many others both Protestant and Catholic, was forced out of a mixed neighborhood by the 1969 violence. Her husband was wounded and became a member of the Protestant paramilitary Ulster Defense Association, as did two of her sons, one of whom is now serving time in the Maza for robbery. A nephew also was imprisoned for murdering a Catholic. She said she tries to keep her youngest son, 16, away from conflict with Catholic toughs on Springfield Road but worries he has little chance of getting a job that will keep him off the streets.

"There is so little for young people to do," said Joe Hendron, a physician who lives and works in the even more improverished and jobless Catholic ghetto on the other side of Springfield Road. "They are susceptible to violence and angry at British Army harassment."

Catholics and Protestants face a common enemy in the steady, steep economic decline of urban northern Ireland, which has been hit even harder by recession and loss of industry than the rest of Britain.

Ulster has Britain's highest unemployment rate -- more than 17 percent overall and more than 50 percent in some of the ghettos -- lowest household income, greatest dependence on government welfare, largest proportion of substandard housing, lowest life expenctancy and highest infant mortality.

Concentration on this gloomy picture and the integral part that sectarian discrimination and conflict play in it is resented by many officials and businessmen, who live in comfortable subsurbs where this May Day holiday weekend means community events and spring gardening rather than the apprehensive watch for violence in the ghetto.

"You keep coming here expecting us to be consumed in fire," said one Belfast business leader. "Well, I'll tell you that no matter what happens because of Sands, we'll still be here when it's over."

An American executive of one of the U.S. firms attracted here by generous British government subsidies and tax breaks said the media was presenting a distorted picture of Northern Ireland and its present crisis that had prompted relatives and friends at home to telephone in alarm about his safety.

"I just say that I'm sitting in my house looking at the cows in the pasture and the cars passing normally on the road," he said.

Better-off Ulster Protestants echoed less crudely the conviction of their counterparts in the ghetto that the Catholic minority, roughly 500,000 people compared to about a million Protestants, was responsible for much of its suffering. Insisting that discrimination is a myth, despite considerable evidence of it, particularly in employment, they castigated Catholics for having large families and living on British government welfare while agitating to join Ulster with the neighboring, overwhelmingly Catholic Republic of Ireland.

No matter how much moderate Catholics disown the IRA terrorists, their continuing support of Irish nationalism encourages the terrorists' hopes of prevailing, argue Protestants from a variety of social backgrounds. They pointed to Sands' April 9 election to a vacant parliamentary seat from an Ulster constituency with a narrow Catholic majority on the border with Ireland.

This important propaganda victory for the IRA was made possible when the other Catholic candidates were maneuvered or intimidated into dropping out against a veteran Protestant Ulster Unionist politician especially unpopular with Catholics.

Catholic political leaders pointed out that the constituency has always divided along sectarian lines. But Harold McCusker, Ulster Unionist member of Parliament from a neighboring rural area, said, "The vote shocked us. Almost all Catholics voted for Sands and that worries us. It puts us in a position of not knowing who we can trust. Did our neighbors vote for the IRA or against the Protestant?"

"Sands' election was a watershed," said a senior official here. "The attention he's gotten as a result, particularly outside northern Ireland, angered the Protestant community and made it less likely to work with the Catholics."

Even if the violence feared when Sands dies can be contained by the security forces with the help of moderating Catholic and Protestant community leaders, this official said, "The political process has been set back badly."

Protestant political leaders had already voiced suspicions about a dialogue recently opened by British Prime Minister Margaret Thatcher and Irish Prime Minister Charles Haughey to increase cooperation between the two countries. The substance of the talks has so far been kept secret. Thatcher has insisted they will not affect Britain's relationship with Northern Ireland, but Haughey and other Irish officials have suggested they could lead to a new approach to the Ulster problem.

Catholic political leaders said they were concerned that the media focus on Sands' hunger strike and the potential for violence might damage their efforts to win peacefully more power and eventually achieve some kind of relationship with Ireland.

"I'm a bit cynical about the international press," said John Hume, leader of the Catholic Social Democratic and Labor Party. "It only comes here when there is a smell of blood, not when the patient work is being done. All this international attention gives the Provos [outlawed Provisional Irish Republican Army members] a big lift. People get on bandwagons."

Every British effort to negotiate a political compromise in which the Protestants and Catholics would share power in the province has been sabotaged by the Protestants' intrasigence to any diminishing of their dominance, by the Catholics' insistence on a tie with Ireland or by the IRA's campaign to trigger a civil war it hopes would force the British out.

"There can be peace only with the status quo," said George Chittick, a Protestant civil servant living on the edge of the west Belfast ghetto who is active in the Orange Order, a staunch defender of majority rule in which Protestants would always outvote Catholics. "You have one million people here who would never allow Ulster to be united with Ireland."

"There will never be peace until this state is abolished" and Ulster is united with Ireland, said Joe Reynolds, a retiree in a Catholic public housing project a mile away. He and other Catholics complained that the British authorities and security forces here underpinned perpetual Protestant dominance with heavy-handed repression in Catholic ghettos.

"Things are certainly no better than they were 10 years ago," said Michael Torrens-Spence, a retired naval officer who lives in the countryside where IRA assassins have frequently struck. "As long as the Irish Republic claims this country and the British government is neutral, we will be unstable because the extremists will believe they can still overthrow it."

British officials said the test for the security forces if there is serious trouble brought on by Sands' death will be whether they are able to protect both the Catholic and Protestant communities from paramilitary attackers from either side. Their greatest concern is community-against-community violence, they said, and escalating "tit-for-tat" sectarian assassinations.

"One of the benefits for us in that task, but one of the tragedies of the troubles," said a senior official, "is that the communities are now so clearly divided from each other."