On the night the lord mayoralty of Dublin changed hands this month, demonstrators protested about refuse charges outside the Mansion House.
Insults were thrown at councillors and aldermen. A few protesters tried to rush the Mansion House doors. Some arriving guests were jostled. One was spat upon. Others were visibly shaken as the mood turned sour.
Although the ranks of the demonstrators included members of other small parties, the majority were from Sinn Fein, acting under the leadership of a recognised, if minor, party figure.
Later, this person was invited inside the Mansion House by a Sinn Fein councillor to enjoy the hospitality of the new Lord Mayor, Cllr Michael Mulcahy, of Fianna Fail. The councillors and guests from the established parties seethed.
The nature of this incident serves to illustrate Sinn Fein's tactics in the Republic: operating inside the system to its advantage but capable, too, of resorting to street politics if necessary.
Fianna Fail, Fine Gael and the Labour Party are unsure of how to tackle the Sinn Fein threat, or even to measure its scale. There is absolute conviction among their strategists, however, that the party with a paramilitary wing will return more than its one TD, Mr Caoimhghin O Caolain, after the next general election. There is less unanimity on whether Sinn Fein will be bidding for a seat in the next government.
What is common to all of the established parties, big or small, is that they are sometimes terrified, frequently frustrated and always irritated by the growing public focus on the party.
In the research for this series, doubts were expressed by many people both inside and outside the political system about Sinn Fein's commitment to fully democratic methods. Some 60 sources - ministers, TDs, advisers, officials, community workers and gardai - were interviewed. All but a handful declined to be named. They were being careful; they didn't want to get involved.
Fianna Fail sources, in particular, were conscious that discommoding Sinn Fein, even locally and in print, could destabilise the bigger peace project.
Sinn Fein's influence in the Republic goes far beyond its size at this juncture, largely because of its pivotal role in the peace process. Judging its real support on the ground is difficult since, unlike other parties, it engages in micropolitics; "every complex, every floor in every complex, every flat on every floor", as one Dublin community worker put it.
Young, committed and well-funded, the Sinn Fein organisation is willing to put in hard work on the ground. In contrast, the grassroots of the larger Dail parties seem old and tired in the face of a public seemingly disillusioned with conventional politics.
Sinn Fein calculates that there will be a quota of discontent in every four-seat and five-seat constituency in the State at the next general election. Whether this will turn to Sinn Fein's advantage is the big question now.
The opinion polls are consistently showing Sinn Fein with a first-preference vote of 6 per cent, through the highs and lows of the peace process, for some time. The mainstream parties argue that Sinn Fein will never make significant inroads in the Republic until the issue of decommissioning is satisfactorily resolved and arms are put beyond use.
Sinn Fein sees a different reality. It believes that it can win target seats or, equally important in its eyes, create beachheads for future campaigns by dealing with local issues and exploiting local grievances.
Taking its three best "hopes" - Cavan-Monaghan, Dublin South West and Kerry North - Sinn Fein clearly believes that IRA decommissioning will matter little, if at all. The party's tactics have accommodated this reality. Their candidate in Dublin South West, Cllr Sean Crowe, for example, talks far less about Northern Ireland than he used to.
If Sinn Fein is on the brink of a breakthrough in the Dail, it will be as a result of years of activity on the ground. In the years before the 1999 local elections, the party, and others allied to it, assumed the role of "local policeman" and used strong-arm tactics in poor areas to discipline "anti-social elements". The tactic found favour with some and intimidated many others. It certainly did Sinn Fein no harm at Killinarden in west Tallaght.
Deprived and troubled, the 1,800 houses on the estate were built by Dublin Corporation on Dublin County Council land in the 1980s. The instantly-assembled new community was left to founder in a hastily-constructed urban wasteland. By the 1990s, the area was drug-infested and crime-ridden. People cried out for action, but little help came from the State. Sinn Fein, its allies and others with no connection filled the social and political vacuum.
"It is easy to see why. You had hundreds of parents, all worried about their kids, and the gardai seen to be doing nothing about it", said one of Sinn Fein's political opponents in Tallaght. The area was ripe for a subtler Southern brand of Sinn Fein's rough justice. Public meetings were called and the "guilty" figures summoned to face angry locals. Non-attendance was not an option.
"The really articulate Sinn Fein person would never be at the top table. They used to be at the back or the front of the hall, but they could get in to say whatever they wanted, whenever they wanted. They ratcheted up the emotions", said a source in attendance.
By 1996, Sinn Fein/IRA members openly controlled traffic in the area using roadside huts. Beatings were frequent, expulsion orders were common and those who dissented were scared into silence.
By degrees, Sinn Fein tried to create its own territories. "For a long time, they prevented normal policing from taking place in Killinarden and Brookfield", according to Cllr Eamonn Walsh, a former Labour TD. "They only have certain patches, but they tried to create environments like they have in Belfast. They marked out an area, dismantled existing services and put in their own."
GARDAI, for example, policed the teenage disco in the Killinarden Community Centre every Friday night for years until they were told by some "community leaders" that they were no longer wanted.
Memories of these public meetings are still vivid. One man, jailed later for five years for drug offences, was brought before a 1,000-strong crowd. "He pleaded for 14 days to sort out his affairs. He asked to be able to see his kids. He was given a half-day a week", a well-known community figure said.
In August 1998, the area was traumatised by the savage killing of a teenager, Ben Smyth, from Cushlawn Park. He was stabbed in the head with a screwdriver by a 15-year-old youth as he sat on a garden wall. A meeting was called. "The ferocity and hatred that night were incredible", said a local politician who was present. "I don't think that anybody at the receiving end of it will ever forget it. The crowd they had organised was frightening."
The situation is changing in places like Killinarden today, even if the social problems are still daunting. Some houses on the estate are now home to three or four wage-earners, but others have not been so lucky.
Throughout Dublin city and county, local authority staff are back in the field, thanks largely to the enlightened policies born from the hard experience of people such as the Dublin City Manager, Mr John Fitzgerald, and many public representatives.
"The drugs marches of five and six years ago showed us that we had lost control", said a city official who is an enthusiastic supporter of the new ideas.
Troubled by Sinn Fein's growing influence and tenants' apathy, Dublin Corporation is organising resident association elections on its estates. The corporation now insists that only two non-residents can occupy chairs on any of its local committees. "We are trying to create a situation where they will feel that they never have to turn to vigilantes again", said an official.
But Sinn Fein's support is real, not dragooned, in many areas. In Dolphin House in Dublin's south inner city, for example, 10 of the 11 residents' committee places were filled by Sinn Fein or its associates. "We don't like it, but democracy is democracy", said a Labour member of the corporation. "That doesn't mean that all of them would be card-carrying members of the republican movement, but they would be influenced by it."
Housing officers now consult local people about incoming tenants, but the days when the locals decided, under Sinn Fein influence, who would get a property seem to be receding.
The corporation has evicted 400 unruly tenants since 1997. "People are beginning to think that they can turn to the corporation and that something will happen", an official said. "The corporation will work with anybody, including Sinn Fein. You can't say that you won't do so. They do a lot of good work." Gardai now appear alongside local authority staff in the community. "It helps if people have a face they can trust", said a Garda source. "We have got to be out there daily."
Policing problems still exist, however. Complaints are still made about Garda "K" District, covering Blanchardstown, Finglas and Mulhuddart, despite recent improvements.
Sinn Fein and its sympathisers are still in control in Marrowbone Lane, in Dublin's south inner city. The Brixton prison escaper Nessan Quinlivan held sway there for some time. The flats complex is clean, well-kept and quiet. Children play safely in a playground kept free of addicts and discarded syringes. Sinn Fein rules there with an iron fist.
"There are a few who think they control these areas OK", said a corporation official, "and that we should let them at it. That attitude must be fought.
"Sinn Fein thrives on crisis situations. They thrive when people turn to them when State agencies are not delivering. That battle will have to be fought every day."
Sinn Fein decided some time ago that it was more profitable politically to work with rather than against local and central government. The softer image began to emerge before the local elections in 1999. Today it is involved with gardai, local authorities and the plethora of task forces set up to counter urban blight. Indeed, the task forces have proved to be a useful source of work for Sinn Fein activists.
Despite the more polite public face, however, intimidation still occurs, although tying Sinn Fein to it is more difficult. If threats rather than "requests" are used, they are made usually by those who appear to be at one remove from the party. They use the cover of "the IRA", "republicans" or "anti-drugs activists".
But the mask slips occasionally. Ken Fitzgerald was given a three-year sentence last May for the theft of a car and receiving stolen goods. In 1998, he was given a two-year suspended sentence, along with two other men, for brutally assaulting a 25-year-old man, Mr John Daffey, in his home.
Mr Daffey's partner and five year-old son were forced to watch. The punishment squad had singled him out after malicious local gossip had wrongly linked him to the drugs trade. The gardai told the court last May that they had never heard of him until the beating.
Fitzgerald, who played a high profile role in the anti-drugs campaigns in Dublin's south inner city in the 1990s, was a Sinn Fein candidate in the last local elections. He received 700 votes in the ward. Once convicted by the Circuit Criminal Court, he promptly went on hunger-strike, claimed membership of the Provisional IRA and demanded a transfer to Castlerea Prison. He got the transfer.
In another incident three or four months ago, a group of armed men gathered around Ballygall Place in Finglas. "They showed off the guns to the young kids. Nobody was beaten up, but nobody complained either", said Mr Sean O Connaith, a respected Ballymun community worker and Workers' Party member. Last February he and party colleagues met the Garda Commissioner, Mr Pat Byrne, and complained that vigilantes in deprived areas were not being prosecuted.
In Kerry North, the Sinn Fein candidate, Cllr Martin Ferris, still insists that he was merely responding to local pleas for help following a spate of thefts around Tralee with his own brand of "community policing". A report was ordered by the Minister for Justice, Mr O'Donoghue. It has remained on the Minister's desk since its completion.
Sinn Fein and the wider republican community are alternatively blamed for, or credited with, actions in different areas because of their past. Sometimes erroneously. "There is a long history here of people taking the law into their own hands", said Mr Pat Carey, Fianna Fail TD for Dublin North West.
In Firhouse, for example, local gossip credits "the IRA" with forcing Travellers to quit an illegal halting site. In reality, the arrival of Revenue and Excise officials may have had more to do with it.
Even Sinn Fein's worst enemies acknowledge that the party works hard on the ground. "Eighty per cent of what they do is valuable", said one Fine Gael politician. The links to vigilantism and the IRA have not disappeared, however, and it remains to be seen whether voters will bring them in from the cold in the Republic.
Tomorrow: Sinn Fein's strategy to win Dail seats