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The political and security situations in Northern Ireland have always been inextricably linked. Since the creation of Northern Ireland in 1921, the majority of its population has traditionally been regarded as unionist or loyalist, meaning that they wish to remain part of the United Kingdom. However, there has always been a significant minority of nationalists or republicans who support a united Ireland and regard themselves as Irish rather than British. Paramilitary organisations on both sides have carried out campaigns of terrorism, most notably during the Troubles, the three decades of conflict from the late 1960s onwards that resulted in over 3,000 deaths.

The nature of the terrorist threat in Northern Ireland has changed significantly in recent years. The Provisional Irish Republican Army (PIRA) and the main loyalist groups have ceased their terrorist campaigns and engaged with the political process. In April 1998 the Good Friday Agreement was signed, paving the way for a devolved Northern Ireland Executive based on power sharing between unionist and nationalist political parties. Although the Executive was suspended in 2002, it was successfully restored in May 2007 and has been in operation ever since.

However, some dissident republican groups reject the political process and the institutions created by the Good Friday Agreement, and continue to carry out terrorist attacks. They seek to destabilise Northern Ireland through the tactical use of violence, targeting members of the Police Service of Northern Ireland (PSNI) and other security personnel as well as seeking to cause disruption and economic damage. They have very little public support.

As the security situation has evolved, so too has the role of MI5 in Northern Ireland. MI5 took on responsibility for national security intelligence work in Northern Ireland in 2007. This brought the national security arrangements in Northern Ireland into line with those in the rest of the UK.

Dissident Republican terrorist groups

Dissident republican terrorist groups pose the most significant threat to national security in Northern Ireland. There are three main dissident republican groups in Northern Ireland: the Continuity IRA (CIRA), the new IRA and Óglaigh na hÉireann (ONH). All have broken away from PIRA at various points, and all oppose the peace process and regard violence as a legitimate means of achieving a united Ireland. Since 2000 dissident republicans have mounted a steady number of attacks in Northern Ireland and between 2009 and 2012 they were responsible for the deaths of two PSNI officers, two British soldiers and a prison officer. Dissident republican attacks often involve collateral risk to members of the public, who are also regularly inconvenienced by the necessary police response to these and other incidents (such as hoaxes).

Aside from attacks against the security forces, dissident republicans also conduct punishment shootings and beatings against alleged criminals in an effort to enhance community support and undermine the PSNI. Many dissident republicans are also heavily involved in criminal activities for personal gain, including smuggling and extortion.

The efforts of the PSNI, working in conjunction with MI5, An Garda Síochána and Army Ammunition Technical Officers, mean that the overwhelming majority of Northern Ireland’s population are able to go about their daily lives untroubled by terrorism. However, although security force pressure is constraining the threat and all dissident republican groups are under pressure, some attacks continue to get through. There were 16 national security attacks in 2015 and the threat to life posed by dissident republicans persists.

International terrorism in Northern Ireland

International terrorism currently poses a severe national security threat to all parts of the UK.

In recent years there have been cases on both sides of the UK-Republic of Ireland border of individuals being charged and convicted of offences related to international terrorism. MI5 and the PSNI work closely with colleagues from An Garda Síochána, the Republic of Ireland’s police force, to counter the threat from international terrorism.

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