On The King David Bombing

From this academic research: "Britain and the Jewish Underground, 1944-46: Intelligence, Policy and Resistance" by Steven Wagner:

The King David Hotel Bombing

Through July, neither MI5 nor the DSO had good information on any illegal armed organizations. Lehi initially was believed to be responsible for the King David  Hotel bombing on 22 July 1946, when the attacker actually was Irgun.424

MI5 continued to believe that the Agency and Irgun were negotiating an agreement, when in fact Irgun, Lehi and Haganah were discussing how to respond to Operation Agatha, which they considered an act of war. Three days before the King David Hotel bombings ‘a most secret source’, which usually meant a form of signals intelligence, indicated that Irgun was believed to be planning an attack against the British officials in Beirut.
425

This threat was taken seriously and all relevant authorities were warned. Both Isham and Giles travelled to Beirut to consult, leaving Jerusalem without its two leading security intelligence officers. Later in life, Isham thought this was a deliberate move by the Irgun.

 Neither the government nor the Army had any sort of warning... on the Saturday two army trucks were stolen, and this was usually the prelude to some form of terrorist activity. Accordingly, I warned General Barker, yourself [John Shaw], and London. Of course we had no idea what was going to be attacked. On the Sunday Morning the High Commissioner was informed by the Colonial Office that it was possible there would be an attack made on [Terrance] Shone, at that time Minister to the Levant States. As a result Giles and myself were asked to go to Beirut to warn Mr. Shone and to see what we could do with the Lebanese police. We did know that a number of the members of the Irgun were in Beirut. I could not help feeling that the Foreign Office report was somehow inspired by Begin...426

It is impossible to say for certain whether or not the threat was real. Since Moyne’s assassination, terrorism abroad was considered a real threat, and was common. If British intelligence was deceived, then Cunningham and his administration were incompetent. Poor security at the King David Hotel was a condition for the bombing. The threat had been evident for years. Even on 29 June, MI5 received indications that Irgun would attack the military and government offices.427

Sherf warned the DSO point-blank that the Irgun “would not wait” to act on its plans.428

The destruction of government headquarters is inexplicable. With one warning after the next, how could it have happened? How many warnings are needed to put extra guards at the entrances? Perhaps it was due to the fact that Giles and Isham were not present to interpret those warnings.

                                                
424
TNA, DSO extract Jewish Affairs. 24.7.46. KV 5/30.101B.
425
TNA, FO to Beirut, 19.7.46. KV 5/36. 107?. Isham to Kellar and Oldfied. 19.7.46. KV 5/36. 107z. Philby to FO. [1]9.7.46. KV 5/36. 108b.
426
NRO, Isham to Shaw, 15.1.72. Isham Papers I 184.
427
TNA, SIME (Sales) to MI5 (Kellar), 29.6.46. KV 5/35. 103a.
428
TNA, Extract from conversations with Sherf 11 and 12 July. 13.7.46. KV 5/30. 100ab.

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