The Ulster Liberation Army (ULA) is an Irish Terrorist organization. They made their only appearance in Patriot Games, but are mentioned in The Sum of All Fears as having been executed. When Jack Ryan stopped their attack on the Prince of Wales and his family they took personal revenge on Jack Ryan and his family. The ULA came into America and came up with attacks that went on for almost a year. Their first attack severely injured Jack's wife and daughter. The matter was resolved when the ULA planned a major attack on Jack's house when the Prince and Princess of Wales were visiting along with his friend, Robby Jackson. The attack caused great damage and the house had to be evacuated and a boat chase ensued, where key members of the ULA were arrested. By the time Jack Ryan became president, all of the surviving members of the ULA had been executed for their crimes.
The ULA is an ultra-violent, Mao-ist offshoot of the Provisional Irish Republican Army (PIRA). There are hints that they are funded by the Soviets.
Sean Miller: Survivor of the attack on the Prince and Princess of Wales. Leader of the team to kill Ryan.
Kevin O'Donnell: Leader of the ULA.
Geoffrey Watkins: Liason between the Foreign Office and the Royal Family, spy for O'Donnell
Shamus Connolly: Infiltrator in the Provisional Irish Republican Army (PIRA)
Attack on the Prince of Wales and Family: Failed; thwarted by Jack Ryan.
Attack on the highway/academy: Ryan's wife and daughter severely injured.
Attack on Ryan's house: Failed and key members of the ULA are arrested.