I remain constantly surprised that this is an issue. Does terrorism work? It depends. Despite Begin's assertions, the Irgun's urban terrorism against Arab civilians and the British authorities wasn't the key to the founding of Israel, but it certainly undermined the Mandate authorities.

Now if Lehi's attempt to bomb the Colonial Office in London and its letter bombs to Harry Truman, Clement Attlee, Winston Churchill, and Anthony Eden had gone off successfully - we might be talking about something else entirely.