The earlier comment about there only being a few cases for extradition being brought before the US judiciary, so the argument goes on to imply such a small number of cases is not all that significant is highly misleading, but probably not fully understood by that poster.
The situation was that a number of murderers escaped from ‘The Maze’ prison.
These had committed their crimes, had been detected and convicted in a proper judicial setting.
When they broke out of prison, they committed another serious criminal act, and as such it was seen by UK that these would amount ot test cases for extradition.
Extradition of Irish terrorists from the US has always been difficult, impossible in
reality and when previous attempts were made to do this, the UK saw which way things were going and decided not to persue such cases further in order not to set legal precedents in the US.
Previous cases were a mix of lesser crimes, of terrorists that had not yet been tried but were wanted for further investigation, or the crimes committed fell into a grey area where there might be a claim that the crime was politically motivated, such offences might have fallen at extradition in US courts.
One powerful group that was protecting Irish terrorist interests were the Kennedys - you may not like it, but its true.
The cases of Maze prison breakouts were, as far as the UK was concerned, about as clear cut as it was possible, convicted with due legal process of the most serious crimes and then escaping from legal custody, it must have seemed to the UK that these would be ideal cases to bring before the US courts.
At first the UK would seem to have faith in US justice restored, since extradition was granted against two of these individuals, however the appeals led to the extradition requests being refused, one of these was on some incredibly threadbare excuse over identity, something like a birthdate being a week out or he right date but the wrong day of the week named, such as Thursday instead of Friday.
On this basis, the UK realised that the US was never going to grant extradition of Irish terorrists, no matter how serious their crimes, and the US would continue to find ways of supporting Irish terrorism, either by not cracking down on the money trail of Irish terrorists, or by not looking too closely at the weapons that were exported from the US to Ireland.
Had the US acted in good faith by extraditing these conviceted murderers, there is little doubt that many more would have followed, so you should not get into the view that since so few cases were brought before the US juduciary, that this is of small significance, in fact it confirmed the US as a place of sanctuary for Irish murderers.
Once these extradition cases failed, those Irish terrorists did not sit on their hands, predictably they did the tour around the clubs and bars, citing themselves as freedom fighters, and using this to assist in fundraising efforts, and while they did this, the US did absolutely nothing at all to intervene, they didn’t track the money not even for taxation purposes.