An article Wednesday said the United Nations had withdrawn 36 American employes of its peace-keeping force from Lebanon at the United States' request. U.S. and U.N. officials have said the withdrawal was ordered by the United Nations.

Only months ago Lebanon looked to the United States as its beacon to peace. But the U.S. veto yesterday of a U.N. resolution condemning Israeli policy in southern Lebanon not only thrust the United States into sharp conflict with the weak ally it had attempted to prop up with arms and the backing of U.S. Marines, it also threatened to increase the vulnerability of U.S. interests and diplomats in Lebanon and throughout the Middle East.

In the face of new threats against the few remaining American diplomats, military officers and journalists still in Lebanon, the United States had labored futilely behind the scenes to prevent the toughly worded resolution condemning Israel's retaliatory raids in southern Lebanon from coming to a vote.

But the Lebanese government insisted on taking the matter to a showdown in the Security Council to demonstrate that it is as deeply concerned about Israel's "iron fist" policy as are the radical Shiites in south Lebanon leading the attacks against the departing Israeli soldiers. The Lebanese government argued unsuccessfully with the State Department that passage of the resolution could serve as a safety valve, defusing the most violent reactions against Israeli forces in Lebanon.

U.S. diplomats, eager not to appear to be undercutting moderate Israeli Prime Minister Shimon Peres, rejected that argument.

"Now is not the time to be throwing stones at an Israeli government that has announced it is withdrawing from Lebanon in stages," said one U.S. official. "I'm sure it would warm the hearts of the Likud if the U.S. were seen to be denouncing Peres." He was referring to the rival Likud party that has formed a government of national unity with Peres' Labor Alignment.

Noting that the attacks on Israeli soldiers increased after Israel began pulling out of Lebanon, he added, "There's a great deal of impatience with this kind of grandstanding" by the Lebanese at the United Nations.

But American and moderate Arab diplomats and analysts agreed that the veto, occurring as it did during Egyptian President Hosni Mubarak's visit to the United States, jeopardizes the faint hopes for some kind of renewal of U.S.-backed efforts to involve Mubarak, Peres and Jordan's King Hussein in revived Middle East peace negotiations.

"It couldn't have come at a worse time," one U.S. official sighed.

"The veto undoubtedly adds to the embarrassment of President Mubarak," said Arab League Ambassador to the United Nations Clovis Maksoud, "because it shows in a rather dramatic way the level of U.S. permissiveness towards Israel in one area where the international community has almost unanimously condemned Israeli behavior and practices."

"We do hope that this is not the entirety of the American position," Maksoud, a Lebanese, added. "Let's attribute it to the last hurrah -- the last veto of Jeane Kirkpatrick."

Although State Department officials had informed a delegation of Arab ambassadors two weeks ago that the United States would veto the resolution, the matter starkly revealed the contradictions in U.S. position in the Middle East.

U.S. policy seeks to accommodate its special ally Israel while also backing Lebanon, Egypt and other moderate Arab states seeking to outflank the fervent Islamic forces that are gaining new prominence in the fight that has pitted Israel against Shiite guerrillas, and now Shiite units of the Lebanese Army.

The U.S. veto left Washington isolated as one of its former partners in the Beirut multinational peace-keeping force, France, voted for it and another, Britain, joined Australia and Denmark in abstaining. France, clearly seeking to retain influence in Lebanon, its former colonial mandate, has not only maintained lightly armed military observers in Lebanon but has offered to expand its contingent in the U.N. force in southern Lebanon.

U.S. military officers and civilian officials working with the U.N. force were withdrawn from Lebanon earlier this month after their lives were threatened if the United States vetoed the resolution. The Reagan administration dispatched two U.S. warships to Lebanon over the weekend to prepare for the possibility that the small group of diplomats, embassy Marine guards and American citizens still in Lebanon should be evacuated.

What was perhaps most surprising about the U.N. vote yesterday was the extent to which the United States and the government of Lebanese President Amin Gemayel have become estranged. U.S. diplomats had rounded up votes in the Lebanese parliament for Gemayel when he was elected president in 1982 and afterwards had acted as his tutor and protector.

But, said a U.S. official yesterday of the current situation, "I think we have a situation in which two governments have their backs up -- we and the Lebanese."