Wikipedia
S-Plan
The S-Plan or Sabotage Campaign or England Campaign was a campaign of bombing and sabotage against the civil, economic, and military infrastructure of the United Kingdom from 1939 to 1940, conducted by members of the Irish Republican Army (IRA). It was conceived by Seamus O'Donovan in 1938 at the request of then IRA Chief of Staff Seán Russell. Russell and Joseph McGarrity are thought to have devised such a strategy in 1936.