If I may chip in my 2p's worth, GnarGnar's assessment is pretty spot on. A dirty war it surely was, and I hope the past tense is the correct one.
Northern Ireland has many levels, from criminals using paramilitary groups as a way of continuing their crimes, to those who feel that they would kill for their political standpoint. It's situation cannot be remotely expressed in a few lines on a forum.
The vast majority of the country has been moving away from the extremes of their viewpoints and becoming increasingly moderate, for want of a better word. Sinn Fein and the DUP sit together in an uneasy government, but sit together they do.
However, it seems there is an increasing number who are going back to the extremes. Those who are disaffected with the majority parties' standpoints, and wish to express themselves albeit in very different ways, for example the TUV and the dissident republican groups. Unionists who have fallen out of love with the DUP, and republicans who will not be happy until NI is integrated into a united Ireland.
It will be interesting to see if the republican side (I assume that this was the source of this disgusting attack EDIT, just found out the Real IRA have claimed responsibilty) manage to help bring the perpetrators to justice. The mainstream republicans have condemned the attack which is at least a step forward.
So where to now? In response to an earlier post, the Republic dont want us (>90% of voters in the republic agreed to give up their territorial claim in exchange for cross border bodies). The majority here want to remain British, and we will do so until the majority vote otherwise (see the St Andrews agreement). What happened last night may well open up old wounds, and thats somewhere I for one would not want to go.
My thoughts and condolences to the families of the bereaved and injured.