DAMASCUS, SYRIA, SEPT. 13 -- The Persian Gulf crisis has accelerated a gradual shift by President Hafez Assad that is ushering his traditionally hard-line Syrian government into closer cooperation with the United States and its main Arab allies.

Assad's transformation in U.S. eyes from shunned sponsor of state terrorism into military ally against Iraq was dramatized by Secretary of State James A. Baker III's arrival here tonight for talks with the Syrian leader. Baker is scheduled to confer Friday with Assad and Foreign Minister Farouk Charaa before flying to Rome on another leg of a tour largely devoted to lining up opposition against Iraq.

But despite tactical agreement that Iraqi President Saddam Hussein's annexation of Kuwait must be reversed, diplomatic sources cautioned, longer-term Syrian and U.S. objectives in the Middle East remain at odds in a number of important areas, particularly the Palestinian conflict and the Golan Heights, which Israel annexed after capturing from Syria in 1967.

It remains to be seen, therefore, whether Syria's current alignment with the United States, Saudi Arabia and Egypt can be extended into broader Middle East diplomacy after the Kuwait crisis subsides.

Assad's 20-year-old rule has always been marked by bitter infighting with Iraq. Damascus and Baghdad, capitals of rival caliphates centuries ago, long have vied for influence in the Arab world and are run by violently opposed wings of the Arab Baath Party. Reflecting the split, Assad cooperated with Iran during its 1980-88 war with Iraq.

In that context, Assad has dispatched about 3,000 Syrian soldiers to Saudi Arabia and 1,000 to the United Arab Emirates as part of the multinational force. Diplomatic sources said he has told Saudi Arabia he will send another armored division if asked, with 10,000 men and about 300 tanks.

"Since we are real nationalists, we must send additional troops to Saudi Arabia and the rest of the gulf countries if they want it," Assad said Wednesday in a speech to army cadets.

Syria's 400,000-man armed forces are equipped with only a dozen AN-12, AN-24 and AN-26 Soviet-made transport planes, making swift deployment of a full division difficult. According to reports here, however, the Soviet Union has offered to assist in airlifting if Saudi Arabia makes a formal request for the armored division.

Saudi Arabia has offered to pay the costs of Syria's military deployment and to inject a large sum of money into its ailing economy in gratitude for Assad's new role, diplomats explained. These funds would be in addition to whatever the Saudis are still paying as subsidies to Arab states confronting Israel under previous Arab summit conference decisions, they said.

In the diplomatic arena, Syria worked closely with Saudi Arabia and Egypt last month in winning Arab League backing for U.S. and other troop deployments in Saudi Arabia. Syrian cooperation also was key in the Arab League's decision Sept. 1 to demand that Iraq not only withdraw from Kuwait, but also pay reparations for damage during and since its Aug. 2 invasion.

"This has particular significance given Assad's Arab nationalist stance and Syria's usual alignment with the so-called radical Arab states," a diplomatic observer pointed out. "It's taken on an entirely new complexion with Syria standing beside Riyadh."

Responding to Iraq's criticism on this point, Assad on Wednesday carefully defended his decision to dispatch Syrian soldiers to stand alongside U.S. and other outside forces on Arab soil. The problem, he said, "is Iraq's occupation of Kuwait, not foreigners in Arab lands."

"Syria is not for the presence of foreign troops anywhere in the Arab world," he continued. "But the issue is not that of foreign troops, because the problem started before the foreign troops came to the area, and it was the problem which brought foreign troops to us."

Aside from enmity with Iraq, Assad has seen several dangers to Syria in Baghdad's takeover of Kuwait, diplomats here said.

Foremost among them is the danger that the Persian Gulf crisis will lead to broader hostilities involving Israel. Assad, who has a long history of conflict with Israel, cannot afford to allow Saddam to make decisions in Baghdad that could plunge Damascus into another Arab-Israeli war not of its own choosing.

Also, Syria's diplomatic position long has been based on the unacceptability under international law of Israeli occupation of the Golan Heights. That position could be undermined if Iraq's annexation of Kuwait were allowed to stand as a precedent that Israel could point to.

The Syrian leader, who has a reputation as a wily player in Middle East contests, had begun to reassess his position even before the current crisis, diplomats here reported. Primarily, he concluded from the Soviet-U.S. warming over the past two years that Moscow could no longer be counted on for military and diplomatic backing againt Israel, they said.

The Soviet Union has continued to provide Assad with modern equipment and warplanes. But since the era of Soviet President Mikhail Gorbachev dawned, Soviet officials have informed him in private and public that they are unwilling to cooperate in his long-standing goal of matching Israel's military strength.

Against that background, Assad increasingly has shown signs of willingness to work with the United States.

Syria, however, remains on the State Department's list of governments connected to state-sponsored terrorism. The 1990 State Department report on terrorism cited Assad's hospitality to Ahmed Jibril, a former Syrian army captain who heads the Damascus-based Popular Front for the Liberation of Palestine-General Command.

Jibril's group has been cited by U.S. officials as the top suspect in the bombing of Pan Am flight 103, which exploded over Lockerbie, Scotland, in December 1988 with the loss of 270 lives. But an international investigation into the bombing so far has failed to produce conclusive evidence of the group's role.