The Sinai Campaign, fought to put an end to terrorist incursions into Israel and to remove the Egyptian blockade of Eilat, marked the final transformation of the IDF into a professional army capable of large-scale operations. A battle plan for the operation was adopted in early October 1956, but was revised following Israel's secret agreement with Britain and France. Under this agreement, Israel would transfer the focus of action as close to the Suez Canal as possible.

On its own account, the Israeli government also drew up a course of action allowing it to convert the operation into a brief raid, should the British and French, contrary to the secret agreement, not intervene. In a new plan, adopted on October 25, it was decided to launch the operation with a paratroop landing, and to hold the Armored Corps back until October 31.

At 17:00 on October 29, Israeli units parachuted into the eastern approaches of the Mitla Pass near the Canal - a political rather than tactical or strategic objective. The action provided the pretext for a French and British ultimatum to Israel and Egypt, calling on both sides to cease hostilities and withdraw from the Canal area. For diversionary reasons, Israeli forces also advanced on southern and central axes.

The following day, October 30, Britain and France issued the planned ultimatum, but to no effect, as heavy fighting between Egyptian and Israeli units persisted. In a swift, sweeping operation of 100 hours, under the leadership of then Chief of the General Staff, Moshe Dayan, the entire Sinai peninsula fell into Israeli hands, at a cost of 231 soldiers killed. Reserve units, about which many misgivings had been uttered before the war, conducted themselves honorably. A reserve brigade, equipped with requisitioned civilian buses, negotiated the difficult desert track and captured Sharm e-Sheikh at the southernmost tip of the Sinai peninsula.
 
The Sinai Campaign did not so much introduce new principles and policies as reaffirm the direction the IDF had already taken. Above all, the doctrine that the determining factors in Israel's mode of warfare would be the Armored Corps and the Air Force was confirmed. The Air Force was still deficient; its development was one of the lessons learned from that war; armor had proven its ability and was there to stay. If 1948 was undoubtedly the War of the Infantry, the uncontested queen of the battlefield in the war of 1956 was Armor.

Once more Israel gained a breathing space of about ten years. Attention now turned to the north, where the Syrians - since 1953 - had been attempting to thwart Israel's National Water Project. Having failed, they undertook to divert the headwaters of the Jordan (originating in Syria), by a manouever designed to leave Israel high and dry. Water is a classical reason for war in the Middle East; but a brief, resolute employment of artillery and tanks prevailed on the Syrians to refrain from their spiteful exercise.

Although Israel had been compelled to withdraw from Sinai without any security guarantee, UNEF - the United Nations Emergency Force, was established to guard against a recurrence of past events. As a result, the fedayun ceased to exist. On the other hand, the Palestine Liberation Organization (PLO), was reorganized and its principal military arm, the Fatah - one of a confusing array of para-military and terrorist organizations - began operations on 1 January 1965, at first from across the Lebanese border. Never an existential threat to Israel, it was a constant nuisance from there on and a temptation to divert attention and energy from the main task, preparations for yet another round.