By early 1964, Arab governments and Palestinian spokesmen had become alarmed by an Israeli project to draw water from Lake Tiberias to irrigate the Negev Desert. Nasser invited the Arab heads of state to attend a summit conference in Cairo in January 1964 at which the principal issue was the Jordan water question. Despite Syria's militant rhetoric, the conference rejected the idea of provoking a war because--it was argued--the Arab states lacked a unified military command. Instead, three alternative courses of action were approved: the diversion of the tributary sources of the Jordan River north of Lake Tiberias in Lebanon and Syria; the establishment of the United Arab Command under an Egyptian commander; and the recognition of the new Palestine Liberation Organization (PLO), headed by a former Jerusalem lawyer, Ahmad Shuqayri (also cited as Shukairi), as the representative of Palestinian resistance against Israel. The Cairo Conference of January 1964 ended in an euphoric atmosphere of goodwill and brotherhood.

Talhuni became prime minister for the second time in July 1964, pledging his government to implement the spirit of the Cairo Conference "according to the king's instructions." Jordan cultivated friendship with Egypt. In May 1965, Jordan joined nine other Arab states in breaking relations with the Federal Republic of Germany (West Germany) because of its recognition of Israel. Jordan and Saudi Arabia signed an agreement in August defining for the first time the boundary between the two countries. Under this agreement, Jordan gave up some territory in the southeast but was able to gain an extension of about eighteen kilometers down the gulf from the crowded port of Al Aqabah.

Almost from the start, trouble developed between the PLO and Hussein's government. Shuqayri, famous for his often hysterical political rhetoric, had organized the PLO in Jerusalem in 1964 with the objective of liberating Palestine in cooperation with all Arab states but without interfering in their internal affairs or claiming sovereignty in the West Bank. Conflict arose because the PLO attempted to assume quasi-governmental functions, such as taxing Palestinians and distributing arms to villagers in the West Bank and among the refugees, acts that infringed on Jordanian sovereignty. The guerrilla organization, Al Fatah, was formed in Damascus with Syrian assistance in December 1957, under the leadership of Yasir Arafat.

Jordanian policy since 1949 had been to avoid border incidents and terrorism that would generate Israeli reprisals. Al Fatah and the PLO, however, carried out raids and sabotage against Israel without clearance from either the United Arab Command or Jordan. These attacks, although planned in Syria, most often were launched into Israel by infiltration through Lebanon or Jordan. Israeli reprisals against selected West Bank targets became harsher and more frequent from May 1965 onward. Meanwhile, Syrian propaganda against Hussein became increasingly strident. In July 1966, when Hussein severed official endorsement and support for the PLO, both that organization and the Syrian government turned against him. In reprisal for the terrorist attacks by the fedayeen (Palestinian guerrillas), in November Israel assaulted the West Bank village of As Samu. Israel was censured by the UN, but public rioting against the Jordanian government broke out among the inhabitants of the West Bank. The levels of rioting exceeded any previous experience. As in the past, Hussein used the army to restore public order. Political pressure against Hussein mounted, however, along with armed clashes on the Syria-Jordan border.

Tension also mounted on the Syria-Israel border, where a land and air engagement took place on April 7, 1967. Syria and Jordan severely criticized Egypt for failing to send support. In mid-May Egypt commenced an extensive military build-up in Sinai in response to Syrian allegations that Syria was in imminent danger of invasion by Israel. Nasser declared a state of emergency on May 16 and two days later demanded removal of the United Nations Emergency Force (UNEF) from Sinai, where it had served as a peacekeeping force since 1957. The UN secretary general acceded to Nasser's demand.

On May 23-24, Nasser announced the closure to Israeli shipping of the Strait of Tiran at the entrance to the Gulf of Aqaba, a measure that Israel immediately declared to be an act of war. Hussein quickly decided that this time it would be impossible for Jordan to stay out of the impending conflict. He hurriedly proceeded to Cairo and on May 30 signed a military alliance with Egypt. Hussein's move represented a response to political pressures at home and the fulfillment of basic pan-Arab commitments. The alliance put the Jordanian army under the field command of an Egyptian general officer.

On June 5, Israel launched a preemptive attack against Egyptian forces deployed in Sinai. The Israeli prime minister, Levi Eshkol, attempted in vain to contact Hussein through UN channels to keep him out of the war. The Egyptian field marshal in overall command of Arab forces ordered Jordanian artillery to open fire on Israeli positions, and Jordan's small air force conducted a bombing raid in the Tel Aviv area. Within hours, however, Israeli warplanes had effectively eliminated the Arab air forces on the ground. After only two days of combat, Jordan's main armored unit had been defeated. Hard fighting continued, as Hussein was determined to hold as much ground as possible in the event that a cease-fire was arranged. By the time he agreed to a truce on June 7, Israeli forces had seized the West Bank and the Old City of Jerusalem.

Of all the Arab belligerents, Jordan, which could least afford it, lost most in the war. Government figures listed over 6,000 troops killed or missing. During the short war, about 224,000 refugees--many of whom had first been refugees from the 1948-49 war--fled from the West Bank to the East Bank. One-third to onehalf of the country's best agricultural land and its main tourist attractions were lost to Israel. On June 27, the Israeli parliament (Knesset) formally annexed the Old City of Jerusalem, an act that the United States and many other nations refused to recognize.

Data as of December 1989