This bombing is an example of a false flag operation. In the British documentary, “The Age of Terror”, you can listen to Israelis admit to dressing like Arabs and blowing up the hotel.
Below is four minutes of a BBC video on the warning (The link has to be changed occasionally due to censorship by guess who).
The King David Hotel bombing (1946-07-22) was a bomb attack against the British Mandate government of Palestine by members of the Irgun, a militant Zionist organization, which was led by Menachem Begin, a future Prime Minister of Israel.
Members of the Irgun, commanded by Yosef Avni and Yisrael Levi  and dressed as ‘Arabs’ and as the Hotel’s distinctive Sudanese waiters, planted a bomb in the basement of the King David Hotel in Jerusalem, part of which was being used as the base for the Mandate Secretariat, the British military headquarters and a branch of the police Criminal Investigation Division. The ensuing explosion caused the collapse of the south-western corner of the southern wing of the hotel. 91 people were killed, most of them staff of the secretariat and the hotel: 28 British, 41 Arab, 17 Jewish, and 5 others. Around 45 people were injured. Some of the deaths and injuries occurred in the road outside the hotel and in adjacent buildings.
The attack on the hotel was the deadliest attack against the British in the history of the Mandate and is often credited as being a major factor in the British decision to relinquish the Mandate. If classed as terrorism, the attack was the most cowardly & deadliest of that kind anywhere in the world.
Prime Minister Clement Attlee commented on the attack to the House of Commons:
Hon. Members will have learned with horror of the brutal and murderous crime committed yesterday in Jerusalem. Of all the outrages which have occurred in Palestine against the Arabs, and they have been many and horrible in the last few months, this is the worst. By this insane act of terrorism 93 innocent people have been killed or are missing in the ruins. The latest figures of casualties are 41 dead, 52 missing and 53 injured. I have no further information at present beyond what is contained in the following official report received from Jerusalem:
“It appears that after exploding a bomb in the street, presumably as a diversionary measure — this did virtually no damage — a lorry drove up to the tradesmen’s entrance of the King David Hotel and the occupants, after holding up the staff at pistol point, entered the kitchen premises carrying a number of milk cans. At some stage of the proceedings, they shot and seriously wounded a British soldier who attempted to interfere with them. All available information so far is to the effect that they were Jews. Somewhere in the basement of the hotel they planted bombs which went off shortly afterwards. They appear to have made good their escape.”
The Zionist Irgun issued an initial statement accepting responsibility for the attack, blaming the British for the deaths due to failure to respond to the warning and mourning only the Jewish victims. A year later, on July 22, 1947, they issued a new statement saying that they were acting on instructions from “a letter from the headquarters of the United Resistance, demanding that we carry out an attack on the British at the King David Hotel as soon as possible.”
In July 2006, Israelis including former Prime Minister Benjamin Netanyahu and former members of Irgun attended a 60th anniversary celebration of the bombing, which was organized by the Menachem Begin Centre. The British Ambassador in Tel Aviv and the Consul-General in Jerusalem dissented, saying “We do not think that it is right for an act of terrorism, which led to the loss of so many lives, to be commemorated.” They also protested against an Israeli plaque that claims that people died because the British ignored warning calls, saying it was untrue and “did not absolve those who planted the bomb.” The plaque read “For reasons known only to the British, the hotel was not evacuated.” City officials agreed to amend the wording on the plaque?