Causes of the Six Day War

Israeli reconnaissance forces from the "Shaked" unit in Sinai during the war.

The causes of the six day war (also called the 1967 war) between Israel and its Arab neighbors are important to understanding Arab-Israeli relations today.

When Israeli nationalists declared the state of Israel in former British Palestine in 1948, surrounding nations argued that it was established illegally. They refused to acknowledge it. This state of tension resulted in open conflict in 1967.

Background to the Six Day War

When Jewish leaders created Israel in 1948, it bordered four Arab nations: Egypt, Jordan, Syria and Lebanon. Israel’s creation outraged Arab citizens, who sympathized with the hundreds of thousands of Arab Christians and Muslims who lost their homes, livelihoods and hopes for political self-determination. They regarded Israel as a European colonial power.

Meanwhile, Israeli citizens felt betrayed by the European colonial powers, who had failed to prevent the Holocaust. Israelis feared that the Jewish people would not survive without the military strength to defend themselves. The new nation had a strong military to defend itself against its Arab neighbors.

In 1956, this distrust broke out in the Suez Crisis, which ended with a stalemate between Egypt and Israel. The United Nations sent a peace-keeping force at the request of Egypt’s President Nasser, to protect the Sinai from another Israeli invasion. Egypt reserved the right to ask this United Nations Emergency Force (UNEF) to leave the Sinai at any time.

The Samu Incident

Arab-Israeli tension was rising in the years just prior to 1967. In 1964 and 1965, Arab presidents and kings met in Cairo, Egypt, to discuss possible military action against Israel. In 1966, a military government came to power in Syria, Israel’s neighbor to the northeast. President Nasser of Egypt, on Israel’s southern border, signed a treaty with Syria agreeing to send military aid if Israel attacked. Israeli leaders regarded these events with suspicion and began preparations for possible war.

In 1965, a group of Palestinian Arabs formed the guerilla military group Fatah, to challenge Israeli control of Palestine. Fatah’s clandestine attacks on Israel led to a serious crisis called the Samu incident.

The Samu incident began on Nov. 11, 1966, when an Israeli patrol close to the Jordanian border encountered a Fatah-planted landmine that killed three soldiers. Israeli leadership responded to the Fatah attack with a rapid, small-scale military incursion into Jordan’s West Bank on Nov. 13. Approximately 600 IDF troops and a dozen tanks crossed the border to the town of Samu, where they dynamited a few dozen houses and public buildings (estimates of the damage vary widely).

Israeli leadership’s rationale for the attack was that Samu’s villagers would demand that Jordan’s King Hussein take action against Fatah to protect Palestinian civilians from further Israeli retaliation. Angry Palestinian citizens of Jordan did criticize King Hussein heavily for failing to protect them. However, their anger led them to support Fatah’s attacks rather than oppose them.

The Samu incident caused great anti-Israeli anger in the Arab media. It also stalled the secret normalization negotiations taking place between Jordan and Israel. It is thus one of the key incidents leading toward the six day war.

Immediate Triggers for the Six Day War

In April 1967, Palestinian guerillas based in Syria launched several rocket attacks on northern Israeli outposts. In addition, a dispute over farming rights along the Syrian border resulted in a number of Israeli-Syrian skirmishes on land and in the air. In April, Israel mobilized 70,000 reserve troops, suggesting it anticipated war. In fact, Israel’s opposition party was pushing Israeli leadership to take action against Syria.

In May 1967, Nasser of Egypt took three significant actions that would lead Israel to make a “preemptive strike.” First, he requested that the UNEF withdraw from the Sinai. The UN complied, as they had no right to remain on Egyptian soil without Egyptian permission.

Nasser then stationed Egyptian troops in the Sinai and blockaded the Straits of Tiran, which gave Israel access to Red Sea shipping lanes. Lastly, on May 30, Nasser signed a military agreement with Jordan. Jordan’s unofficial détente with Israel was over.

Within Israel, public opinion feared the nation was in danger of Arab conquest. However, historical documents show that Israel’s government, led by Prime Minister Levi Eshkol and Defense Minister General Moshe Dayan, thought in terms of Israel’s long-term foreign policy as they debated their next move.

On June 5, Israel launched an assault on Egypt, Syria and Jordan.

Debates about the Causes of the Six Day War

Some historians argue that the Arab military alliances of 1967 made it imperative for Israel to take pre-emptive military action. They posit that the blockade of the Straits of Tiran was a belligerent act requiring a belligerent response.

Other historians disagree. They argue that Egypt, Syria and Jordan mobilized their armed forces in response to Israeli mobilization and that they did not intend to provoke a war for which they were poorly prepared.

What is undeniable is that both sides wanted to make a show of strength. Their maneuvering resulted in a war with long-term consequences for everyone involved.


  1. Arthur Goldschmidt, Jr., and Lawrence Davidson, A Concise History of the Middle East, 8th ed. Westview Press (2005).
  2. Ilan Pappé, A History of Modern Palestine Cambridge University Press (2006).