So let's just summarise the history of Northern Ireland over the last ten years.
All the terrorists that previous governments had managed to catch and convict have been given amnesties and let out of jail. Their former apologists have become members of the government. The army presence has been scaled down from 30,000 soldiers to 5,000. The checkpoints and watchtowers have been pulled down and taken away. The RUC (Royal Ulster Constabulary) has been wound up and replaced by the Northern Ireland Police Service - the only police force in the country afraid to wear royal insignia. Meanwhile the IRA's massive arsenal of weaponry has been "put beyond use", which the British government chose to regard as much the same as surrendering the weapons.
Then on the evening of Saturday last (March 7th, 2009) the IRA attacked Massereene Barracks and killed two members of 38 Royal Engineers regiment, and wounded two others. Two pizza delivery persons were also injured, one very badly.
There seems to be some doubt as to whether the attack was by the "Real IRA" or the "Continuity IRA" or some other IRA-like group.
But there can be no doubt that letting them out of jail was a bad idea.