Michael McGibbon was given an order he couldn’t refuse: go to an alley at 10 o’clock and take your punishment. The reason for the summons from the masked men who came to his door the previous evening remains unclear. Minutes after he arrived to face the paramilitaries who had summoned him, the 33-year-old father of four lay dying in the arms of his wife, Joanne, a nurse, who heard the shots and was first on the scene.

"This killing bears all the hallmarks of a paramilitary murder," said police Detective Superintendent John McVea in the wake of the execution. "Those who carried it out have no legitimacy in this community and today I am asking the community to help us find them. Help us bring justice to the McGibbon family."

His appeal, like so many others over the years in Northern Ireland, appears to have fallen on deaf ears: almost a month later nobody has been charged.

Last Monday night Dan Murray, a takeaway delivery driver, was lured to a house in west Belfast by a bogus call. The 55-year-old father of six was shot in the head and died instantly. He had survived a previous murder attempt. His murder was the fourth gun attack in the city in just four days. A 38-year-old man was arrested in connection with the killing but later released. Detectives have now arrested a second man.

The latest police figures released on Friday show that security forces dealt with an average of a bomb attack every week over the past year - an increase of 44% over the previous corresponding period. There were 52 bomb-related incidents in 2014/15 compared with 36 the previous year.

Dissident republicans have been ratcheting up their activities. In March, prison officer Adrian Ismay died days after after a bomb exploded under his van on his way to work and during the week the government increased the threat level of an attack on mainland Britain from "moderate" to "substantial", which means MI5 now considers there is "a strong possibility" one will take place.

Since the formation of various armed dissident groups in the wake of the Good Friday Agreement in 1998 that effectively ended three decades of bloody conflict, hundreds of their members have been jailed in Northern Ireland and the Republic. Assistant police chief Will Kerr said in March that the force was stopping as many as four planned dissident attacks for every one that succeeded.

The security forces are believed to have successfully penetrated the ranks of the dissident organisations at all levels but they admit that intelligence will never be able to prevent every attack.

Despite the increased concern of a potential attack in England, Scotland or Wales, in numerical terms it is the nationalist communities in Northern Ireland that have been bearing the brunt of those who oppose the reunification of Ireland by peaceful means. Since the turn of the year, republican paramilitaries have been implicated in four murders of Catholic civilians for unspecified reasons as well as numerous so-called punishment shootings and beatings.

Aside from mounting sporadic operations on the security forces, dissident republicans continually prey on their own communities: running extortion rackets, engaging in widespread intimidation, meting out summary justice to petty criminals and those they allege to be involved in anti-social behaviour and drug offences.

A recent study published in the journal, Terrorism and Political Violence, concludes that the overwhelming majority - 77% - of the 175 people shot dead or wounded by armed dissident republicans from 2007-2015 fell into the category of 'Catholic and/or criminal'.

Sinn Fein leader Gerry Adams has insisted repeatedly that "the IRA has left the stage" but some of its actors have clearly refused to retire and are now directing a younger generation.

The police have so far failed to fill the vacuum left by the demise of the IRA, which often used similar tactics as those now being employed by dissidents in nationalist areas during the Troubles. The organisation announced a formal stand-down in 2005 and Sinn Fein, its erstwhile political wing that now shares power in the Stormont assembly, said it would support the police two years later.

Since then, many more Catholics have joined the Police Service of Northern Ireland, which operates an affirmative action policy to encourage greater recruitment from the minority community that was hostile to its predecessor, the Royal Ulster Constabulary, which was an overwhelmingly Protestant, unionist force.

A former IRA member in the Sinn Fein stronghold of west Belfast who spoke on the basis of anonymity told the Sunday Herald that almost a decade later, nationalist community distrust of the force remained.

"People simply don't trust them because at the higher ranks at least it is clear they still regard the war as a criminal act and by extension continue to regard us as criminals," he said. "I'll put it this way – if someone was up to something around here I wouldn’t be contacting the police to sort it out."

In a statement Sinn Fein said its representatives continued to engage with the police at all levels, including working on community safety initiatives.

"At the very highest level Sinn Fein’s Martin McGuinness, the deputy First Minister, has stood publicly beside successive chief constables in order to face down threats to the peace process," it said.

Fr Gary Donegan, the outspoken rector of Holy Cross parish in Ardoyne, describes the dissidents as cowardly criminals but argues that there must be engagement with them to persuade them of the damage their activities were inflicting on their own communities and the futility of continuing their attacks on security forces.

"With the vast, vast majority of these people, if you asked them if their motivation was ideological and if they were fighting for a united Ireland based on the socialist principles of James Connolly or Karl Marx they would look at you as if you had two heads," he says. "A lot of these guys running around at the moment would have trouble following a plot on Sesame Street."

Fr Donegan, 52, who carries a bullet-proof vest and claims he "could paper his walls with the death threats he has received over the years from both loyalist paramilitaries and dissident republicans", says that in many ways the disenchantment with the police in the working-class community where he ministers would be similar in other such areas in cities across the world, including Glasgow and Edinburgh.

"The difference here is that a 14-year-old who is causing trouble might need a good kick up the backside but he certainly doesn't need to be taken down an alley and shot – that's what's happening here and it has to stop."