JERUSALEM, JAN. 19 (SATURDAY) -- Israel may abandon its policy of restraint from direct military action in the Persian Gulf War as a result of a second Iraqi missile strike on the country early today, according to senior government sources.

"A retaliation now is almost inevitable," Health Minister Ehud Olmert told Israel radio.

"This time they will not escape again," said one senior official. He would not say what action Israel might take, but added, "It's going to be an interesting day."

Under strong pressure from the United States and its Persian Gulf allies, the government of Prime Minister Yitzhak Shamir decided Friday against immediate retaliatory action for the first Iraqi missile attack that slammed into the center of the country. The decision was made in part because of what U.S. commanders said was an all-out effort by allied forces to destroy the Scud missiles and mobile launchers that still remained in Iraqi hands.

However, in the aftermath of this morning's second attack, officials said they no longer felt bound by their initial commitment to Washington. "The fact is that the American military has failed to fulfill its promise to Israel," the senior official said.

Israel's initial restraint was heavily qualified. Officials stressed Friday that the country was only delaying, not forgoing, retaliatory action against Iraq and would eventually punish Baghdad. They also said the government would reconsider its position if Iraq managed to strike again.

Israel "maintains the right to react, in the scope, the means and the time it finds necessary," Foreign Minister David Levy said Friday. "That's the elementary right of every state."

In a television appearance last night, Foreign Minister Moshe Arens said: "We told the Americans before the war that we would respond if attacked, and we were attacked. We will respond." But he added: "I won't say when."

Another senior government official stated the government's initial policy more clearly, on condition he not be named. "We are not going to play into the hands of Saddam Hussein, who wants to drag us into this conflict and bring about a clash between us and Jordan and Syria, and create problems for the United States," the official said Friday evening. "We are not going to leave this attack unanswered. But on the other hand, it's not necessary for us to do anything hasty."

In effect, this source said, Israel had agreed Friday to accept the risk of absorbing a second Iraqi strike before taking any action of its own. Before the war began, Israel effectively resigned itself to taking a first blow by pledging not to launch a preemptive attack on Iraqi missiles.

The missile attacks have confronted Shamir's government with an acute political and strategic dilemma, officials said. Having repeatedly pledged publicly that it would respond to any such attack, the government feels compelled for reasons of both domestic politics and regional reputation to follow through on its words.

At the same time, government and military officials acknowledged that an Israeli attack would run the risk of widening the Persian Gulf War and weakening the U.S.-led alliance against Iraq, especially if Israeli planes became involved in clashes with Jordanian and Syrian forces on their way to Iraq. Both countries have warned Israel not to attack Iraq and vowed they would resist the movement of warplanes through their airspace.

There were some signs that Israel came to the brink of launching a retaliatory strike Friday morning immediately after the initial Iraqi blow. One military official told several reporters Friday morning that Israeli planes were on their way to "take Iraq apart." An hour later he retracted the information, saying action had been postponed at the last minute.

Official sources confirmed that Shamir received a telephone call from Secretary of State James A. Baker III between 5.00 and 5.30 a.m. Friday. A senior aide to Shamir said the two men spoke for about five minutes, and that Baker asked for Israeli restraint.

Despite the decision to postpone action Friday, senior government officials said Israel and the United States still had not reached an understanding about Israeli action in the future. "Israel at the request of the United States has been taking a lot of risks," one official said. "We are trying to reach a kind of understanding with the United States on this whole question, but I don't know if we will be able to continue."

Shortly before the onset of war last weekend, Shamir rebuffed a U.S. request that Israel commit itself not to respond to any Iraqi attack. Following two days of meetings here between senior government officials and a delegation led by Deputy Secretary of State Lawrence Eagleburger, Washington implicitly acknowledged that Israeli military action might be unavoidable, agreeing to set up tactical coordination between Israeli forces and U.S. commanders in the gulf.

Political and military officials here stressed Friday that the nature and timing of Israeli action against Iraq depended greatly on Washington's ability to halt further Iraqi missile strikes on Israeli cities. In political terms, officials said, a second unanswered Iraqi blow was unthinkable, especially if it caused more civilian casaulties.

"This is not baseball," said an American Jewish activist in Jerusalem. "Two strikes and this government is out."

"It would be immoral and foolish for us not to respond," said an official close to Shamir. "It would send a message to the Arab world that we are weak and indecisive."

Emotional pressures for a response were underscored by a former head of Israeli military intelligence, Gen. Shlomo Gazit, who told NBC-TV this morning that "Israel's credibility depends on if we do or do not respond" to the attacks. While the United States is better set to attack the missile launchers, he said: "We can retaliate, which you won't. . . . It may be against civilian centers or strategic targets."

In military terms, another successful Iraqi attack on Israel could exhaust the patience of commanders anxious to use the country's own formidable air power to liquidate Baghdad's offensive capability. "We want to ensure that nothing and no one in western Iraq can raise its head off the ground without getting it blasted off," said a military source.

Unlike U.S. forces in Saudia Arabia, Israel does not now have the capacity to shoot down incoming Iraqi missiles with the Patriot air defense system. Although two batteries of Patriots arrived in the country this month, Israeli crews have not finished training to use the system. U.S. officials have been quoted as saying the Israeli Patriot system may not be operative against incoming missiles until April.

Government officials said that eventually Israeli retaliation against Saddam was certain. "We have to do something, and our only decision is what and when," an official said. "If there is another Iraqi attack in the meantime it will just add to the Iraqi pain at the end of the day."

Some observers here speculated that Israel might sidestep the political and military problems of a conventional air raid on Iraq by adopting an unorthodox course of action, such as mounting a commando raid or some kind of covert action.