The war was against Syria, Jordan and Egypt. Israel believed that it was only a matter of time before the three Arab states co-ordinated a massive attack on Israel. After the 1956 Suez Crisis, the United Nations had established a presence in the Middle East, especially at sensitive border areas. The United Nations was only there with the agreement of the nations that acted as a host to it. By May 1967, the Egyptians had made it clear that the United Nations was no longer wanted in the Suez region. Gamal Nasser, leader of Egypt, ordered a concentration of Egyptian military forces in the sensitive Suez zone. This was a highly provocative act and the Israelis only viewed it one way – that Egypt was preparing to attack. The Egyptians had also enforced a naval blockade which closed off the Gulf of Aqaba to Israeli shipping.
Rather than wait to be attacked, the Israelis launched a hugely successful military campaign against its perceived enemies. The air forces of Egypt, Jordan, Syria and Iraq were all but destroyed on June 5th. By June 7th, many Egyptian tanks had been destroyed in the Sinai Desert and Israeli forces reached the Suez Canal. On the same day, the whole of the west bank of the Jordan River had been cleared of Jordanian forces. The Golan Heights were captured from Syria and Israeli forces moved 30 miles into Syria itself.
The war was a disaster for the Arab world and temporarily weakened the man who was seen as the leader of the Arabs – Gamal Abdul Nasser of Egypt. The war was a military disaster for the Arabs but it was also a massive blow to the Arabs morale. Here were four of the strongest Arab nations systematically defeated by just one nation.
The success of the campaign must have surprised the Israelis. However, it also gave them a major problem that was to prove a major problem for the Israeli government for decades. By capturing the Sinai, the Golan Heights and the West Bank of the Jordan River, the Israelis had captured for themselves areas of great strategic value. However, the West Bank also contained over 600,000 Arabs who now came under Israeli administration. Their plight led many young Arabs into joining the Palestinian Liberation Organisation (PLO), a group that the Israelis deemed a terrorist organisation. Israeli domestic policies became a lot more complicated after the military successes of June 1967.
http://www.newworldencyclopedia.org/entry/Six-Day_War
http://www.britannica.com/EBchecked/topic/850855/Six-Day-War
Wikipedia??? Really??