It is only the second conviction of its kind
Real IRA leader Seamus McGrane has been jailed for eleven-and-a-half years for plotting a bomb attack during the visit of Prince Charles to Ireland.
The 63-year-old, with an address of Dromiskin, Co Louth, was arrested after being put under surveillance in early 2015.
He was secretly recorded making plans with another man in the snug of a pub near Dublin airport.
Outside court afterwards, Detective Chief Superintendent Tom Maguire praised all those who brought about what’s only the second conviction of its kind.
He explained: "I want to just acknowledge the work that has gone into this operation from the investigation team at the Special Detective Unit, allied to the whole security and intelligence family... people who in the normal course of events never get mentioned due to the nature of the work that they do."
"It's just another example of An Garda Síochana's ability and determination to investigate terrorism, both from a domestic perspective and in relation to any international terrorism."