The Israelis were upbeat, the Americans guardedly optimistic, and the Lebanese both hopeful and skeptical. After more than 15 hours of talks with the Israeli and Lebanese foreign ministers, US Secretary of State George P. Shultz appears to have moved the two sides slightly closer to an agreement on foreign troop withdrawals from Lebanon. Part of the price for the United States has been an American commitment to increase, if necessary, the US troop presence and training role in Lebanon.
But more is at stake in the outcome of the withdrawal talks than pulling foreign troops out of Lebanon. The Americans are convinced that King Hussein of Jordan will not come into negotiations over the Palestinian question unless there is clear movement toward a withdrawal of Israeli troops from Lebanon. From Washington's point of view, American credibility in the Arab world is at stake.
Israeli Foreign Minister Yitzhak Shamir's trip to Washington was taken at the initiative of his own government. It is widely believed that the Israelis were unhappy with Philip Habib, the chief American negotiator in the Middle East. By sending Mr. Shamir to Washington, the Israelis apparently hoped to go over Mr. Habib's head in the hope of finding more understanding for their positions from Mr. Shultz and President Reagan. According to both US and Lebanese officials, this tactic didn't work. Shultz brought Habib into the Washington talks, and Habib played a key role, apparently, in formulating new American ideas aimed at moving the negotiations forward.
But even as the gap between the Israelis and Lebanese seems to be ever so slightly closing, differences seem to persist. The Israelis insist on keeping a presence in southern Lebanon even after their regular battalions go home.
The Israelis want to maintain a link with the only troops they trust in southern Lebanon, the Israeli-supplied Lebanese militiamen under the command of Maj. Saad Haddad. The Lebanese government has long regarded Major Haddad as a renegade, but moves aimed at integrating his forces into the Lebanese Army are now under consideration.
Much now depends on what Shamir takes back to his Israeli Cabinet colleagues and on how the Cabinet, at its meeting March 20, decides to react to new ideas presented to Shamir by Shultz.
Whatever the outcome, a great deal of negotiating may have to be done. But the Americans hope Moshe Arens, the new Israeli defense minister, will prove to be more flexible on the Lebanon question than was his predecessor, Ariel Sharon.
The Americans and the Lebanese contend that the Lebanese Army is now much improved and capable of securing southern Lebanon. The Israelis don't believe them. But the Americans and Lebanese counter that where the Lebanese Army has taken over, calm prevails; the only areas where major violence is occurring are areas under foreign occupation, either Israeli or Syrian.
Lebanese officials continued talks in Washington on March 16 following Shamir's departure. One member of the Lebanese delegation said he feared the Israelis were trying to drag out the talks over Lebanon in order to delay US-proposed negotiations over the Palestinian issue and the Israeli occupation of the West Bank of the Jordan River.
But one problem, as the Israelis see it, is this: Once the Israelis withdraw from Lebanon, what incentive will the Lebanese have to keep negotiating over a ''normalization'' of relations with Israel? Thus while Israel appears to be dropping its demand for a normalization agreement, or diplomatic relations, prior to its withdrawal, it will insist that Lebanon firmly commit itself to future negotiations and steps toward normalization.
On the question of security in southern Lebanon, the Israelis were expected to propose some form of joint patrolling that would include Israelis. They have apparently dropped their demand that Israeli observation posts be established in a southern Lebanon security zone.
But American officials point out that any permanent Israeli presence in southern Lebanon will make it difficult for the US and Lebanon to persuade the Syrians to withdraw their forces from the embattled country.