In early 1987, both superpowers indicated their interest in the security of the region. Soviet deputy foreign minister Vladimir Petrovsky made a Middle East tour expressing his country's concern over the effects of the Iran-Iraq War. In May 1987, United States assistant secretary of state Richard Murphy also toured the Gulf emphasizing to friendly Arab states the United States commitment in the region, a commitment which had become suspect as a result of Washington's transfer of arms to the Iranians, officially as an incentive for them to assist in freeing American hostages held in Lebanon. In another diplomatic effort, both superpowers supported the UN Security Council resolutions seeking an end to the war (see Foreign Policy , ch. 4).

The war appeared to be entering a new phase in which the superpowers were becoming more involved. For instance, the Soviet Union, which had ended military supplies to both Iran and Iraq in 1980, resumed large-scale arms shipments to Iraq in 1982 after Iran banned the Tudeh and tried and executed most of its leaders. Subsequently, despite its professed neutrality, the Soviet Union became the major supplier of sophisticated arms to Iraq. In 1985 the United States began clandestine direct and indirect negotiations with Iranian officials that resulted in several arms shipments to Iran.

Iranian military gains inside Iraq after 1984 were a major reason for increased superpower involvement in the war. In February 1986, Iranian units captured the port of Al Faw, which had oil facilities and was one of Iraq's major oil-exporting ports before the war.

By late 1986, rumors of a final Iranian offensive against Basra proliferated. On January 8, Operation Karbala Five began, with Iranian units pushing westward between Fish Lake and the Shatt al Arab. They captured the town of Duayji and inflicted 20,000 casualties on Iraq, but at the cost of 65,000 Iranian casualties. In this intensive operation, Baghdad also lost forty-five airplanes. Attempting to capture Basra, Tehran launched several attacks, some of them well-disguised diversion assaults such as Operation Karbala Six and Operation Karbala Seven. Iran finally aborted Operation Karbala Five on February 26.

In late May 1987, just when the war seemed to have reached a complete stalemate on the southern front, reports from Iran indicated that the conflict was intensifying on Iraq's northern front. This assault, Operation Karbala Ten, was a joint effort by Iranian units and Iraqi Kurdish rebels. They surrounded the garrison at Mawat, endangering Iraq's oil fields near Kirkuk and the northern oil pipeline to Turkey.

By late spring of 1987, the superpowers became more directly involved because they feared that the fall of Basra might lead to a pro-Iranian Islamic republic in largely Shia-populated southern Iraq. They were also concerned about the intensified tanker war. During the first four months of 1987, Iran attacked twenty ships and Iraq assaulted fifteen. Kuwaiti ships were favorite targets because Iran strongly obje485 jected to Kuwait's close relationship with the Baghdad regime. Kuwait turned to the superpowers, partly to protect oil exports but largely to seek an end to the war through superpower intervention. Moscow leased three tankers to Kuwait, and by June the United States had reflagged half of Kuwait's fleet of twenty-two tankers. Finally, direct attacks on the superpowers' ships drew them into the conflict. On May 6, for the first time, a Soviet freighter was attacked in the southern Gulf region, hit by rockets from Iranian gunboats. Ten days later, a Soviet tanker was damaged by a mine allegedly placed by Iranians near the Kuwait coast. More shocking to the United States was the May 17 accidental Iraqi air attack on the U.S.S Stark in which thirty-seven sailors died. The attack highlighted the danger to international shipping in the Gulf.

Data as of December 1987