Israel’s recent airstrike in Syria, which according to Western officials targeted weapons destined for the militant Lebanese group Hezbollah, could mark the start of a more aggressive campaign by Israel to prevent arms transfers as conditions in Syria deteriorate, according to analysts in Israel and Lebanon.

Israel’s readiness to strike again if necessary heralds a new and more volatile phase in the regional repercussions of Syria’s civil war, which has raised concerns in Israel about the possible transfer of advanced or nonconventional weapons to Islamist militant groups.

Israeli Defense Minister Ehud Barak all but acknowledged that Israel carried out the strike near Damascus on Jan. 30, saying it was “proof that when we say something we mean it.” An Israeli cabinet minister had warned before the attack that Israel could act against transfers of chemical weapons to militant groups.

Amos Yadlin, a former chief of Israeli military intelligence who directs the Institute for National Security Studies in Tel Aviv, said in an interview that while future Israeli action could be expected, it would depend on specific calculations of the advantages and risks of such strikes.

Four types of weapons

Israel, he said, has defined four types of weapons whose transfer to militant groups would not be tolerated: advanced air defense systems, ballistic missiles, sophisticated shore-to-sea missiles and chemical weapons.

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In accordance with this policy, Yadlin said, “any time Israel will have reliable intelligence that this is going to be transferred from Syria to Lebanon, it will act,” although specific decisions to strike would be subject to assessments of the military value of the attack, the risk of escalation and the positions of foreign powers.

“As the Syrian army becomes weaker and Hezbollah grows more isolated because of the loss of its Syrian patron, it makes sense that this will continue,” Yadlin said, adding that Israeli responses would be weighed each time and “not happen automatically.”

The real dilemma facing Israeli officials, Yadlin said, is not whether to attack, but whether inaction would mean a greater threat later. “The correct comparison is the risk of escalation now and the risk of having a much more formidable enemy and many casualties in future hostilities,” he said.

Analysts in Lebanon also predicted more Israeli strikes if advanced weapons transfers were attempted.

“Israel is trying to create a sense of deterrence,” said Elias Hanna, a retired general and a professor at the American University of Beirut. “The other side tries to test and erode the system.”

According to Israeli assessments, Hezbollah has amassed about 60,000 rockets and missiles since a 2006 war with Israel. Israeli officials say these include some Scud-D ballistic missiles, with a range of more than 400 miles, supplied by Syria in recent years. Along with other shorter-range missiles from Syria and Iran, Hezbollah’s arsenal can reach anywhere in Israel, the officials say.

The transfer to Hezbollah of advanced antiaircraft systems, such as the SA-17 ground-to-air missiles said to have been the target of the Jan. 30 strike, would not only threaten Israel’s reconnaissance flights over Lebanon but also Israeli airspace, according to an Israeli official monitoring the buildup of such weapons.

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“They are mobile. They can be hidden and can pose a very big problem for the Israeli air force,” said the official, who is not authorized to speak to the media.

The Israelis say they are also concerned about the possible transfer to Hezbollah of coastal missile systems supplied to Syria by Russia, specifically Yakhont cruise missiles with a range of more than 180 miles, which could endanger not only Israeli vessels but also Israeli oil rigs in the Mediterranean. In the 2006 war, an Israeli naval ship was hit by a Chinese-designed shore-to-sea missile fired by Hezbollah.

As the fighting in Syria intensifies, “there are more tangible indications that such weapons could reach Lebanon,” the official said.

Syria’s chemical weapons arsenal, including bombs and rockets tipped with chemical warheads, remains for now under government control, according to Israeli assessments.

“The [intelligence] monitoring of the Syrian chemical weapons depots is quite strict, so there’s a fairly good chance that any movement would be detectable,” said Dany Shoham, a former military intelligence analyst and an expert on unconventional weapons at the Begin-Sadat Center for Strategic Studies at Bar-Ilan University.

Escalation risks

Nizar Abdul Kader, a Lebanese analyst and retired general, said that Israeli reconnaissance missions are keeping an eye on roads between Syria and Lebanon and that any preparation for movement of advanced weaponry is likely to provoke an Israeli strike. He said Hezbollah has stored heavy weapons and long-range missiles in Syria but is not likely to expose them by transferring them under current conditions.

With the Syrian army preoccupied with internal fighting and Hezbollah wary of jeopardizing its position in Lebanon as its Syrian sponsor weakens, neither is likely to risk wider conflict by retaliating against Israel for the Jan. 30 strike, according to the Israeli official and analysts.

“The Syrians are interested in keeping the civil war in Syria, where they are militarily much stronger than the rebels,” Yadlin said. “Against external forces, they would be inferior.”

“If Hezbollah attacked [Israel], they would basically be admitting that the air defense system was on its way to them, infuriating the Russians” who supplied the weapons to Syria with the understanding that they would not be moved to Hezbollah, he said.

Still, Yadlin cautioned, every additional Israeli strike would raise the risk of escalation.

“The decision makers have to reevaluate every time,” he said. “It’s not a mathematical equation.”

Dehghanpisheh and Suzan Haidamous reported from Beirut.