JERUSALEM — In a letter to President Bush, Prime Minister Yitzhak Shamir has set the limits of Israel's patience with missile attacks from Iraq, saying Israel will retaliate if rockets kill greater numbers of civilians or if chemical warheads are used.
"I am sure you assess that if an attack on us will cost a significant number of lives, or an attack waged in which a non-conventional warhead is used, it would create an intolerable situation which would require an immediate response on our part," Shamir wrote in the letter delivered Monday.
Brief excerpts from the letter were leaked here Tuesday as Israeli jets, for the first time in the Gulf War, bombarded bases of the Palestine Liberation Organization and other Palestinian groups, killing eight and wounding 28, Lebanese authorities said.
Israeli officials say Shamir wrote Bush to make clear that, in certain circumstances, Israel would retaliate with or without Washington's approval, although he promised to "consult." Bush has pressured Shamir to restrain his air force so the war with Iraq is not widened, and Arab allies--notably Syria--that are hostile to Israel are not tempted to switch sides.
"We are quite eager to retaliate," said an aide to Shamir. "What would you do if someone slapped you in the face in the street? You would want to hit him back."
The official declined to give a number of casualties or fatalities that would automatically trigger an Israeli response, except to say, "Until now, we have been lucky. But imagine if there are dozens of fatalities. Pressure would be enormous."
In 10 separate volleys, 30 Iraqi Scud missiles targeted at Israel have killed two Israelis and wounded scores of others, mostly with flying glass. All the missiles have carried explosive warheads. Property damage is estimated to total at least $30 million. Another 12 citizens have suffocated or suffered heart failure during air raids because of improper use of gas masks.
"There is an assessment here that Iraq, if desperate, will try to launch chemical weapons to create psychological if not physical damage," added another senior official. "We felt we should make our response known in advance, especially to Washington."
Officials said that full tactical coordination with the United States is not yet in place but is "nearing the desirable level."
In Washington, a White House official confirmed that Bush received a letter from Shamir. He said he could not divulge the contents but added that the message as described by Israeli sources "is pretty much what they've said in the past."
Bush agreed that an attack on Israel with chemical weapons would give Israel legitimate grounds to retaliate, the official added.
"We believe a chemical attack would understandably be provoking," he said.
Asked whether the United States and Israel had worked out any procedure for military cooperation if Israel attacks Iraq, the official said: "There has been plenty of discussion, but I don't know of any final decision."
If Israel's air force were to strike at targets in Iraq, it would presumably request the electronic codes used by the U.S. Air Force in the area so that American and other allied aircraft would recognize the Israelis and not shoot them down.
U.S. officials have said that Israel was deliberately not given those codes after the first Scud missile attacks against Tel Aviv on Jan. 18. Officials have also said the codes are changed frequently, so that Israel would apparently need to ask shortly before mounting any air attack.
Shamir's letter was described by Israeli officials as an effort to establish an operational Red Line, a term used here to mark the tripwire for Israeli action. In the past, any attack across Israel's borders was considered the red line for retaliation, but the threshold has become blurred during the Gulf War. Shamir instituted a policy of restraint so as not to upset the American war plan.
Shamir's task in setting the conditions of Israel's entrance to the war had been made somewhat less urgent by a pair of allied actions: First, the United States has been busy trying to knock out Iraq's missile launchers, making it questionable whether Israel could do much more; second, the effectiveness of Patriot anti-missile systems delivered to Israel helped allay public nervousness.
In a survey released Tuesday, 80% of the public supported Israel's policy of restraint.
But an aide to the prime minister said, "In the event of casualties, public opinion would change in a minute."
There have been insistent murmurings among military officers that Israel must unleash its own forces, if for no other reason than to show Arab enemies they mean business.
Air force chief Avihu Bin-Nun described at least one tactic Israel might use to deter missile attacks: Put bombers in the skies over the launch sites at all times. "The most effective way to remove the missile threat to Israel is nonstop action," he said, "while demonstrating aerial presence in areas in which the missiles are fired."