The IRA are considered by some the innovators of modern terrorism as the British would replicate and build upon the tactics used against by the IRA in World War II . Tony Geraghty in '' The Irish War : The Hidden Conflict Between the IRA and British Intelligence '' wrote : From January 1939 to March 1940 , the Irish Republican Army ( IRA ) carried out a campaign of bombing and sabotage against the civil , economic , and military infrastructure of Britain . It was known as the S-Plan or Sabotage Campaign . During the campaign , the IRA carried out almost 300 attacks and acts of sabotage in Britain , killing seven people and injuring 96 . Most of the casualties occurred in the Coventry bombing on 25 August 1939
Coventry bombing
1939 Coventry bombing
History of terrorism