Israeli Prime Minister Yitzhak Shamir's visit here next week is developing into one of the most important US-Israeli encounters to date. But US State Department officials are warning that no dramatic changes are expected in the US-Israeli relationship.
By playing down the outcome of the Shamir visit in advance, the officials may be engaging in the old diplomatic game of lowering expectations to make whatever happens look like an accomplishment.
But officials also stress that there are limits to how far the United States can go in plans for ''strategic cooperation'' with Israel because this nation has ''contending interests'' in the Middle East, namely a need for friendship with Arab states. A further brake on such cooperation is Defense Department reluctance to engage in it.
What seems clear, however, is that the United States and Israel share a growing concern about a Soviet-supplied arms buildup in Syria and are entering the opening stages of a higher level of cooperation. Such cooperation is partly aimed at issuing a warning to Syria.
''One of the ways to deter the Syrians is to send a signal that we are working closely with the Americans,'' said an Israeli official involved in preparations here for the Shamir visit Nov. 27-29.
The Israelis are eager to make their cooperation with the United States more public and more formal. As one official put it, the idea would be to ''take the relationship out of the closet.''
The Israelis are interested in, among other things, reaching agreements on joint military maneuvers with US forces in the region and on the stockpiling, or ''prepositioning,'' of American defense equipment in Israel for possible US use in a crisis. Israeli officials point out that the US has engaged in joint exercises with Egyptian air and ground forces but not with Israeli forces.
Israeli military analysts say that Syria's Army has sharply increased in size over the past two years, and that this has been accompanied by a major increase in Soviet-supplied, high-quality military equipment.
But as the Middle East Policy Survey, published here, pointed out recently, the ''common thread'' running through all the proposed plans for closer US-Israeli strategic cooperation - including cooperation against Syria - is the need for Defense Department agreement and participation.
Defense Department officials have argued that proposals for enhanced cooperation with Israel tend to work against plans for cooperation with friendly Arab nations, such as Saudi Arabia.
Told at a breakfast meeting with reporters recently that Washington was buzzing with reports of a new strategic cooperation agreement with Israel, Secretary of Defense Caspar W. Weinberger said, ''The fact that the whole town is buzzing doesn't necessarily mean that anything is about to happen.''
Asked if a decision had been made to work more closely with Israel, the defense secretary made it sound as though the relationship would continue to move along much as before.
''I think there's been a continuing set of decisions that we would continue to work very closely with Israel, as we have since the formation of the country, '' Weinberger said.
''Basically, our national interests have been served for a long time by working closely with Israel,'' he continued. ''I would certainly expect and assume and hope we would continue to do that.
''I would also expect and hope and assume that we would recognize that we need many friends in the Middle East and that we believe we can best bring peace to that area, as the President has said, by ensuring that those relationships continue and flourish.''