Serious military planning was being devoted in Whitehall to war with Israel. The chiefs of staff endorsed an elaborate scheme called Operation Cordage on January 26 1956. The Israeli airforce was to be caught on its airfields and smashed by a substantial air contingent based on Cyprus, a naval blockade was to be imposed, and carrier-based planes would harass the Israeli forces from the air while commando raids would be undertaken along the coast. A scheme to seize Eilat, Israel's window on to the Red Sea, was added later. Under Operation Cordage, substantial British naval and air forces were kept at the ready. Once the Suez crisis was under way very much the same forces - though with a different command structure - were also assigned to Operation Musketeer, which was to be directed against Nasser.
Ariel Sharon's reprisals against Jordan were getting more severe as the Suez crisis moved on. On October 10, General Templer, the chief of the imperial general staff, felt that it that it should be brought home "very forcibly" to ministers that "we can either go to the aid of Jordan against Israel, or we can launch Musketeer; we cannot do both". Eden's relief was unfeigned at the paragraph in the protocol of Sèvres that Israel would not attack Jordan.
The second ghost issue was the belief that the two atomic superpowers would always cut a deal and let the other parties go to hell. When the British and French summoned a conference in response to the nationalisation of the Suez Canal Company, Nasser wanted to go straight to the UN security council to complain about the steps being taken against Egypt. Shepilov, the new Soviet foreign minister, approved, but was overridden on the grounds that the Soviet Union should instead accept the invitation to the London conference.
The ghost reappeared on November 6 1956 when Konrad Adenauer, the German chancellor, was in the office of Guy Mollet, the French prime minister, negotiating the treaty of Rome. News came through that Eden had ordered a ceasefire after speaking to President Eisenhower. Adenauer broke into a long anti-American tirade, the gist of which was that for two and a half years Eisenhower had had back-channel communications with the Kremlin. Here was the outcome. He told Mollet: "We have no time to waste: Europe will be your revenge."
· Keith Kyle is the author of Suez: Britain's End of Empire in the Middle East. An exhibition of Suez cartoons from Britain, Egypt and Israel runs until September 1 in the Guardian Newsroom.