Michele Chabin, Kate Shuttleworth and Oren Dorell, USA TODAY
JERUSALEM - Millions of Israeli children started their first day of school Tuesday and people went about their daily routines, though a sense of anxiety was in the air.
Once again a possible U.S. attack on an Arab nation threatened to place a target on Israel, which has paid a price in the past when the West acts militarily in the Middle East.
The prime minister issued warnings to enemies, the army held exercises on the border and lines formed for gas masks. Yet supermarkets, restaurants, theaters and beaches were as lively as ever, and welcoming ceremonies for schoolchildren were held outdoors.
"This is Israel," said Adi Lipkin, a high school teacher shopping for a hat in a Jerusalem clothing store. "There's a crisis every couple of years, so we don't get worked up until there's really something to worry about."
The United States and its allies hinted Tuesday that the regime of President Bashar Assad may be attacked militarily for the alleged gassing of his people to halt a rebellion. Israeli papers were full of threats from enemies that it would be Israel that pays for any military operation against Assad.
Syrian Baath national council member Halef al-Muftah said that Damascus views Israel as "behind the aggression and therefore it will come under fire" should Syria be attacked for an alleged gas attack that killed hundreds of civilians.
In an interview for the American radio station Sawa in Arabic, al-Muftah, Assad's former propaganda minister, said: "We have strategic weapons and we can retaliate. Essentially, the strategic weapons are aimed at Israel," reported Ynet News in Jerusalem.
Iran also warned it would blame Israel if the United States goes after Assad.
"No military attack will be waged against Syria," said Hossein Sheikholeslam, a member of Iran's Islamic Consultative Assembly, according to the Times of Israel. "Yet if such an incident takes place, which is impossible, the Zionist regime will be the first victim of a military attack on Syria."
Israel has not armed or taken active involvement in the rebellion to its north and has limited its actions in Syria to missile strikes against two convoys of purported weapons being driven to its arch-enemy Hezbollah in southern Lebanon.
That may not matter. Israel's largest city, Tel Aviv, and Haifa, its main seaport, were hit by scud missiles from Iraq in retaliation for the 1991 Gulf War launched by President George H.W. Bush. Hezbollah fired rockets at Israel throughout the U.S.-led Iraq War.
To counter the threat, Israeli Prime Minister Benjamin Netanyahu said in a televised statement that Israel would "respond powerfully" if Syria or any nation tries to do it harm.
Netanyahu called a surprise meeting of his security Cabinet during the day - his second of the week - and then publicly warned Assad's government to not seek any reprisal against Israel.
"Israel is not a part of the civil war in Syria, but if we identify any attempt to hurt us, we will respond, and respond powerfully," he said.
The Israel Defense Forces began a pre-planned two-day drill in the Golan Heights involving security and emergency forces, where area residents expected to hear the sounds of gunfire and explosions, according to the newspaper Israel Hayom.
Patriot anti-missile batteries in Haifa have been put on alert and aimed toward the north, it said. The Knesset Homefront Preparedness Subcommittee was to hold a special meeting on Wednesday to examine readiness for a Syrian attack.
"The state's duty is to be ready for any scenario," Knesset member Eli Yishai, the subcommittee chairman, told Israel Hayom.
The threats by Iran and Syria are not idle ones, and could have drastic repercussions, said Ariel Cohen, an expert on Russia and Central Asia at the Heritage Foundation in Washington.
Cohen says Syria has tons of chemical weapons and thousands of rockets it can fire at Tel Aviv and other Israeli cities. And Iranian-backed Hezbollah in Lebanon has as many as 100,000 rockets aimed at Israel.
A massive rocket onslaught would overwhelm Israel's missile defense system and could lead to mass Israeli civilian casualties - and a devastating Israeli response, Cohen said.
"If Syria responds with chemical weapons, Israel may respond asymmetrically," he said, alluding to nuclear weapons.
Israel, which is not a signatory to the Nuclear Non-Proliferation Treaty, is widely believed to possess several hundred nuclear warheads. The chance of it using nukes in such a counterattack on Syria "is low, but not zero," Cohen said.
Some Israelis said they were jittery, and there has been a run on gas masks in recent days. The Tel Aviv Stock Exchange dropped amid war fears.
Sigalit Beangio, a mother of four, was in line for masks at a mall and said she was also stocking up on bottled water and canned food. Odelya Kaplan, 30, had been waiting in a line for an hour.
"I don't know what is going to happen, but to be safe I came to get the masks for my family, that's all I can do," she said.
Maya Avishai of the Israeli Postal Service, which handles the distribution of gas masks, said the number of people who requested gas masks at distribution centers or by phone had increased fourfold this week.
Scott Young, 57, an American from Virginia living in Jerusalem, was waiting for his mask.
"It's better to be safe than sorry," he said.
Karako Rami, from Modiin, an Orthodox Jewish settlement and city in the West Bank, said he felt that Syria could attack Israel.
"I don't really know for sure, but it's so dangerous and we have four kids," he said.
Yechiel Kuperstein, a former head of the IDF's Home Front Command's Physical Protection Department & Development Department, said that Israelis trust their government to give them fair warning of an impending security meltdown.
"People see that politicians are talking but that nothing is happening," Kuperstein said. "We have enough experience to know that if something is really brewing, the authorities will let us know and give us enough time to prepare for it."
Until now, Kuperstein noted, Home Front Command hasn't issued any special instructions to the public. If and when it does, Israelis know what to do, he said.
"If tensions soar and there is a risk of attack, people will be told to check their bomb shelters and stock up on supplies. But right now, there are no special announcements and no need to do anything special."
Al-Muftah warned in an interview on the Iranian channel al-Alam that if the United States or Israel try to "exploit" the chemical issue, "the region will go up in endless flames, affecting not only the area's security, but the world's."
Syria would attack Israel if hit by the U.S. because Israel is the entity that pulls the Americans' strings, he said, according to a transcript published by the Jewish Telegraphic Agency.
Dorell reported from McLean, Va.