By May 1967, Israel believed an Arab attack was imminent; Egyptian President Gamal Abdel Nasser had ordered a withdrawal of U.N. peacekeeping forces on the border and announced a blockade of Israeli goods through the Straits of Tiran. At the same time, Syria increased border confrontations along the Golan Heights and mobilized its troops. Israel withheld military action due to a request by the United States, but international diplomatic efforts to stop the blockade failed. The Arab states began to mobilize their troops, and Arab leaders called for a war of total destruction against Israel.
Arab mobilization compelled Israel to mobilize its own troops, 80 percent of which were reserve civilians. Israel launched a pre-emptive strike against Egypt on June 5. Israel captured the Sinai Peninsula and the Gaza Strip from Egypt, and when Jordan and Syria entered the conflict Israel also gained control of the West Bank and the eastern sector of Jerusalem from Jordan and the Golan Heights from Syria. In a catastrophic military defeat – which shook the Arab world for many years to come – the Arab nations ceased their fight six days after the war began.
This new territory brought great changes to Israeli daily life and created new challenges for policymakers. With the reunification of Jerusalem, Jews, who were prevented by Jordan from entering the eastern part of the city, flocked to pray at the Western Wall for the first time in 19 years. In the West Bank and Gaza Strip, Israel had to grapple with the implications and challenges of having one million Palestinian Arabs now under its control.